{"name": "Ticks search index", "description": "A curated corpus of constraint-dissolving moments. One row per tick.", "homepage": "https://ticks.iamkesava.com/", "license": "https://opensource.org/licenses/MIT", "version": "2026-05-03T08:01:25.308Z", "count": 2648, "items": [{"id": "recursive-language", "name": "Recursive language", "year": "70,000 BC", "yearN": -70000, "zone": "cognitive-leap", "domain": "language", "constraint": "communication limited to immediate reality", "parents": 1, "children": 7, "url": "https://ticks.iamkesava.com/#/walk/recursive-language"}, {"id": "collective-fiction", "name": "Collective fiction", "year": "70,000 BC", "yearN": -70000, "zone": "cognitive-leap", "domain": "philosophy", "constraint": "cooperation limited to kin groups (~150 people)", "parents": 1, "children": 8, "url": "https://ticks.iamkesava.com/#/walk/collective-fiction"}, {"id": "cave-painting-symbolic-art", "name": "Cave painting / symbolic art", "year": "40,000 BC", "yearN": -40000, "zone": "cognitive-leap", "domain": "art", "constraint": "knowledge transfer limited to direct demonstration", "parents": 3, "children": 6, "url": "https://ticks.iamkesava.com/#/walk/cave-painting-symbolic-art"}, {"id": "burial-ritual", "name": "Burial ritual", "year": "40,000 BC", "yearN": -40000, "zone": "cognitive-leap", "domain": "religion", "constraint": "death as a purely physical event", "parents": 3, "children": 3, "url": "https://ticks.iamkesava.com/#/walk/burial-ritual"}, {"id": "bone-flute-intentional-music", "name": "Bone flute / intentional music", "year": "30,000 BC", "yearN": -30000, "zone": "cognitive-leap", "domain": "art", "constraint": "sound as functional signal only", "parents": 2, "children": 4, "url": "https://ticks.iamkesava.com/#/walk/bone-flute-intentional-music"}, {"id": "wheat-domestication", "name": "Wheat domestication", "year": "10,000 BC", "yearN": -10000, "zone": "settled-world", "domain": "agriculture", "constraint": "food supply as contingent on movement", "parents": 4, "children": 3, "url": "https://ticks.iamkesava.com/#/walk/wheat-domestication"}, {"id": "animal-domestication", "name": "Animal domestication", "year": "10,000 BC", "yearN": -10000, "zone": "settled-world", "domain": "agriculture", "constraint": "protein requiring active hunting", "parents": 2, "children": 5, "url": "https://ticks.iamkesava.com/#/walk/animal-domestication"}, {"id": "pottery-fired-clay", "name": "Pottery / fired clay", "year": "9,000 BC", "yearN": -9000, "zone": "settled-world", "domain": "agriculture", "constraint": "food storage limited to immediate consumption", "parents": 4, "children": 4, "url": "https://ticks.iamkesava.com/#/walk/pottery-fired-clay"}, {"id": "irrigation-canals", "name": "Irrigation canals", "year": "8,000 BC", "yearN": -8000, "zone": "settled-world", "domain": "agriculture", "constraint": "farming limited to rainfall patterns", "parents": 3, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/irrigation-canals"}, {"id": "fermentation-beer-and-bread", "name": "Fermentation (beer and bread)", "year": "7,000 BC", "yearN": -7000, "zone": "settled-world", "domain": "agriculture", "constraint": "grain as perishable raw material", "parents": 3, "children": 3, "url": "https://ticks.iamkesava.com/#/walk/fermentation-beer-and-bread"}, {"id": "loom-weaving", "name": "Loom weaving", "year": "5,000 BC", "yearN": -5000, "zone": "settled-world", "domain": "economics", "constraint": "fabric production requiring hand-knotting", "parents": 4, "children": 6, "url": "https://ticks.iamkesava.com/#/walk/loom-weaving"}, {"id": "the-wheel", "name": "The wheel", "year": "3,500 BC", "yearN": -3500, "zone": "settled-world", "domain": "economics", "constraint": "load transport requiring human or animal carrying", "parents": 3, "children": 6, "url": "https://ticks.iamkesava.com/#/walk/the-wheel"}, {"id": "cuneiform-writing", "name": "Cuneiform writing", "year": "3,400 BC", "yearN": -3400, "zone": "settled-world", "domain": "language", "constraint": "memory and record limited to what a human brain holds", "parents": 5, "children": 6, "url": "https://ticks.iamkesava.com/#/walk/cuneiform-writing"}, {"id": "trepanation-skull-drilling", "name": "Trepanation (skull drilling)", "year": "3,100 BC", "yearN": -3100, "zone": "settled-world", "domain": "medicine", "constraint": "the skull as inviolable and impenetrable", "parents": 4, "children": 7, "url": "https://ticks.iamkesava.com/#/walk/trepanation-skull-drilling"}, {"id": "egyptian-hieroglyphics-phonetic-principle", "name": "Egyptian hieroglyphics (phonetic principle)", "year": "3,100 BC", "yearN": -3100, "zone": "settled-world", "domain": "language", "constraint": "writing as pure logography", "parents": 2, "children": 5, "url": "https://ticks.iamkesava.com/#/walk/egyptian-hieroglyphics-phonetic-principle"}, {"id": "mesopotamian-clay-tablet-record-keeping", "name": "Mesopotamian clay-tablet record-keeping", "year": "3,000 BC", "yearN": -3000, "zone": "first-civilizations", "domain": "economics", "constraint": "transactions surviving only in living memory", "parents": 4, "children": 7, "url": "https://ticks.iamkesava.com/#/walk/mesopotamian-clay-tablet-record-keeping"}, {"id": "city-state-governance", "name": "City-state governance", "year": "3,000 BC", "yearN": -3000, "zone": "first-civilizations", "domain": "law", "constraint": "social order requiring personal authority of a known leader", "parents": 6, "children": 5, "url": "https://ticks.iamkesava.com/#/walk/city-state-governance"}, {"id": "pyramid-construction", "name": "Pyramid construction", "year": "2,600 BC", "yearN": -2600, "zone": "first-civilizations", "domain": "art", "constraint": "monumental architecture as impossible for human labor", "parents": 8, "children": 4, "url": "https://ticks.iamkesava.com/#/walk/pyramid-construction"}, {"id": "akkadian-empire-first-empire", "name": "Akkadian Empire (first empire)", "year": "2,350 BC", "yearN": -2350, "zone": "first-civilizations", "domain": "law", "constraint": "political order limited to a single city or valley", "parents": 6, "children": 4, "url": "https://ticks.iamkesava.com/#/walk/akkadian-empire-first-empire"}, {"id": "babylonian-quadratic-equations", "name": "Babylonian quadratic equations", "year": "1,770 BC", "yearN": -1770, "zone": "first-civilizations", "domain": "philosophy", "constraint": "equations requiring geometric intuition to solve", "parents": 3, "children": 7, "url": "https://ticks.iamkesava.com/#/walk/babylonian-quadratic-equations"}, {"id": "code-of-hammurabi", "name": "Code of Hammurabi", "year": "1,750 BC", "yearN": -1750, "zone": "first-civilizations", "domain": "law", "constraint": "justice as personal and arbitrary", "parents": 5, "children": 5, "url": "https://ticks.iamkesava.com/#/walk/code-of-hammurabi"}, {"id": "alphabetic-writing-phoenician", "name": "Alphabetic writing (Phoenician)", "year": "1050 BC", "yearN": -1050, "zone": "first-civilizations", "domain": "language", "constraint": "writing requiring years of specialist training", "parents": 5, "children": 6, "url": "https://ticks.iamkesava.com/#/walk/alphabetic-writing-phoenician"}, {"id": "monotheism-akhenaten", "name": "Monotheism (Akhenaten)", "year": "1,350 BC", "yearN": -1350, "zone": "first-civilizations", "domain": "religion", "constraint": "divine power as distributed among competing gods", "parents": 4, "children": 3, "url": "https://ticks.iamkesava.com/#/walk/monotheism-akhenaten"}, {"id": "bronze-age-trans-regional-trade", "name": "Bronze Age trans-regional trade networks", "year": "1,300 BC", "yearN": -1300, "zone": "first-civilizations", "domain": "economics", "constraint": "long-distance exchange as one-shot expedition rather than sustained circuit", "parents": 4, "children": 3, "url": "https://ticks.iamkesava.com/#/walk/bronze-age-trans-regional-trade"}, {"id": "iron-smelting", "name": "Iron smelting", "year": "1,200 BC", "yearN": -1200, "zone": "first-civilizations", "domain": "war", "constraint": "metal tools limited by bronze's rare ingredient (tin)", "parents": 3, "children": 4, "url": "https://ticks.iamkesava.com/#/walk/iron-smelting"}, {"id": "greek-alphabet-with-vowels", "name": "Greek alphabet with vowels", "year": "800 BC", "yearN": -800, "zone": "first-civilizations", "domain": "language", "constraint": "reading requiring contextual knowledge to decode", "parents": 3, "children": 7, "url": "https://ticks.iamkesava.com/#/walk/greek-alphabet-with-vowels"}, {"id": "coined-money-lydia", "name": "Coined money (Lydia)", "year": "600 BC", "yearN": -600, "zone": "axial-age", "domain": "economics", "constraint": "trade requiring barter or weighing commodity metals", "parents": 4, "children": 4, "url": "https://ticks.iamkesava.com/#/walk/coined-money-lydia"}, {"id": "pre-socratic-natural-philosophy", "name": "Pre-Socratic natural philosophy", "year": "580 BC", "yearN": -580, "zone": "axial-age", "domain": "philosophy", "constraint": "natural phenomena requiring divine explanation", "parents": 4, "children": 5, "url": "https://ticks.iamkesava.com/#/walk/pre-socratic-natural-philosophy"}, {"id": "buddhism-four-noble-truths", "name": "Buddhism (Four Noble Truths)", "year": "563 BC", "yearN": -563, "zone": "axial-age", "domain": "religion", "constraint": "suffering as imposed by gods or fate", "parents": 3, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/buddhism-four-noble-truths"}, {"id": "confucianism", "name": "Confucianism", "year": "551 BC", "yearN": -551, "zone": "axial-age", "domain": "philosophy", "constraint": "social order requiring divine mandate or force", "parents": 2, "children": 6, "url": "https://ticks.iamkesava.com/#/walk/confucianism"}, {"id": "p-inis-sanskrit-grammar", "name": "Pāṇini's Sanskrit grammar", "year": "500 BC", "yearN": -500, "zone": "axial-age", "domain": "language", "constraint": "language as describable only by example, not rule", "parents": 3, "children": 7, "url": "https://ticks.iamkesava.com/#/walk/p-inis-sanskrit-grammar"}, {"id": "athenian-democracy", "name": "Athenian democracy", "year": "500 BC", "yearN": -500, "zone": "axial-age", "domain": "law", "constraint": "legitimate political authority requiring hereditary or divine origin", "parents": 6, "children": 3, "url": "https://ticks.iamkesava.com/#/walk/athenian-democracy"}, {"id": "socratic-method", "name": "Socratic method", "year": "400 BC", "yearN": -400, "zone": "axial-age", "domain": "philosophy", "constraint": "knowledge as received from authority", "parents": 4, "children": 5, "url": "https://ticks.iamkesava.com/#/walk/socratic-method"}, {"id": "sushruta-samhita-surgical-manual", "name": "Sushruta Samhita (surgical manual)", "year": "400 BC", "yearN": -400, "zone": "axial-age", "domain": "medicine", "constraint": "surgery as ad-hoc and untransmissible", "parents": 3, "children": 3, "url": "https://ticks.iamkesava.com/#/walk/sushruta-samhita-surgical-manual"}, {"id": "aristotles-formal-logic", "name": "Aristotle's formal logic", "year": "350 BC", "yearN": -350, "zone": "axial-age", "domain": "philosophy", "constraint": "argument as purely rhetorical", "parents": 4, "children": 5, "url": "https://ticks.iamkesava.com/#/walk/aristotles-formal-logic"}, {"id": "euclids-elements", "name": "Euclid's Elements", "year": "300 BC", "yearN": -300, "zone": "axial-age", "domain": "philosophy", "constraint": "mathematical truth as empirical or approximate", "parents": 4, "children": 4, "url": "https://ticks.iamkesava.com/#/walk/euclids-elements"}, {"id": "heliocentric-model-aristarchus", "name": "Heliocentric model (Aristarchus)", "year": "270 BC", "yearN": -270, "zone": "axial-age", "domain": "philosophy", "constraint": "Earth as center of the universe", "parents": 4, "children": 3, "url": "https://ticks.iamkesava.com/#/walk/heliocentric-model-aristarchus"}, {"id": "archimedes-statics-and-buoyancy", "name": "Archimedes / statics and buoyancy", "year": "250 BC", "yearN": -250, "zone": "axial-age", "domain": "physics", "constraint": "physical phenomena as describable only qualitatively", "parents": 3, "children": 6, "url": "https://ticks.iamkesava.com/#/walk/archimedes-statics-and-buoyancy"}, {"id": "roman-roads", "name": "Roman roads", "year": "312 BC", "yearN": -312, "zone": "axial-age", "domain": "war", "constraint": "army movement speed limited by terrain", "parents": 5, "children": 4, "url": "https://ticks.iamkesava.com/#/walk/roman-roads"}, {"id": "codex-format-bound-pages", "name": "Codex format (bound pages)", "year": "100 AD", "yearN": 100, "zone": "classical-empires", "domain": "language", "constraint": "text requiring sequential reading from a scroll", "parents": 4, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/codex-format-bound-pages"}, {"id": "rosetta-stone-parallel-text-decipherment", "name": "Rosetta Stone / parallel text decipherment", "year": "196 BC", "yearN": -196, "zone": "classical-empires", "domain": "language", "constraint": "ancient scripts as permanently undecipherable", "parents": 4, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/rosetta-stone-parallel-text-decipherment"}, {"id": "ptolemys-coordinate-system", "name": "Ptolemy's coordinate system", "year": "150 AD", "yearN": 150, "zone": "classical-empires", "domain": "society", "constraint": "maps as schematic and non-projectable", "parents": 15, "children": 3, "url": "https://ticks.iamkesava.com/#/walk/ptolemys-coordinate-system"}, {"id": "paper-cai-lun-han-dynasty", "name": "Paper (Cai Lun, Han Dynasty)", "year": "105 AD", "yearN": 105, "zone": "classical-empires", "domain": "language", "constraint": "writing requiring expensive or heavy materials", "parents": 3, "children": 6, "url": "https://ticks.iamkesava.com/#/walk/paper-cai-lun-han-dynasty"}, {"id": "symbolic-algebra-notation-diophantus", "name": "Symbolic algebra notation (Diophantus)", "year": "250 AD", "yearN": 250, "zone": "classical-empires", "domain": "philosophy", "constraint": "equations requiring full verbal description", "parents": 4, "children": 6, "url": "https://ticks.iamkesava.com/#/walk/symbolic-algebra-notation-diophantus"}, {"id": "edict-of-milan-christianity-legalized", "name": "Edict of Milan / Christianity legalized", "year": "313 AD", "yearN": 313, "zone": "classical-empires", "domain": "religion", "constraint": "Christianity as an illegal cult subject to periodic persecution", "parents": 6, "children": 1, "url": "https://ticks.iamkesava.com/#/walk/edict-of-milan-christianity-legalized"}, {"id": "muhammad-prophetic-call", "name": "Muhammad / a prophet for the Arabs", "year": "570 AD", "yearN": 570, "zone": "post-classical", "domain": "religion", "constraint": "Arabian peninsula as a tribal world without a unifying scripture", "parents": 4, "children": 1, "url": "https://ticks.iamkesava.com/#/walk/muhammad-prophetic-call"}, {"id": "arabic-numerals-and-zero", "name": "Arabic numerals and zero", "year": "800 AD", "yearN": 800, "zone": "post-classical", "domain": "economics", "constraint": "arithmetic impossible with Roman numeral system", "parents": 4, "children": 5, "url": "https://ticks.iamkesava.com/#/walk/arabic-numerals-and-zero"}, {"id": "algebra-al-khwarizmi", "name": "Algebra (al-Khwarizmi)", "year": "820 AD", "yearN": 820, "zone": "post-classical", "domain": "philosophy", "constraint": "equations solvable only case-by-case", "parents": 4, "children": 6, "url": "https://ticks.iamkesava.com/#/walk/algebra-al-khwarizmi"}, {"id": "canon-of-medicine-avicenna", "name": "Canon of Medicine (Avicenna)", "year": "1025 AD", "yearN": 1025, "zone": "post-classical", "domain": "medicine", "constraint": "medicine as tradition-bound and unsystematic", "parents": 3, "children": 5, "url": "https://ticks.iamkesava.com/#/walk/canon-of-medicine-avicenna"}, {"id": "optics-and-experiment-ibn-al-haytham", "name": "Optics and experiment (Ibn al-Haytham)", "year": "1000 AD", "yearN": 1000, "zone": "post-classical", "domain": "medicine", "constraint": "vision as the eye projecting light outward", "parents": 3, "children": 4, "url": "https://ticks.iamkesava.com/#/walk/optics-and-experiment-ibn-al-haytham"}, {"id": "musical-staff-notation-guido-darezzo", "name": "Musical staff notation (Guido d'Arezzo)", "year": "1025 AD", "yearN": 1025, "zone": "post-classical", "domain": "art", "constraint": "music transmission requiring memorization", "parents": 10, "children": 5, "url": "https://ticks.iamkesava.com/#/walk/musical-staff-notation-guido-darezzo"}, {"id": "university-as-institution", "name": "University as institution", "year": "1088 AD", "yearN": 1088, "zone": "post-classical", "domain": "law", "constraint": "advanced knowledge requiring monastic or court patronage", "parents": 7, "children": 3, "url": "https://ticks.iamkesava.com/#/walk/university-as-institution"}, {"id": "fibonaccis-liber-abaci", "name": "Fibonacci's Liber Abaci", "year": "1202 AD", "yearN": 1202, "zone": "post-classical", "domain": "economics", "constraint": "European commerce using Roman numerals", "parents": 4, "children": 5, "url": "https://ticks.iamkesava.com/#/walk/fibonaccis-liber-abaci"}, {"id": "magna-carta", "name": "Magna Carta", "year": "1215 AD", "yearN": 1215, "zone": "post-classical", "domain": "law", "constraint": "royal authority as unlimited", "parents": 4, "children": 4, "url": "https://ticks.iamkesava.com/#/walk/magna-carta"}, {"id": "eyeglasses", "name": "Eyeglasses", "year": "1286 AD", "yearN": 1286, "zone": "post-classical", "domain": "medicine", "constraint": "presbyopia as the end of intellectual productivity", "parents": 4, "children": 4, "url": "https://ticks.iamkesava.com/#/walk/eyeglasses"}, {"id": "mechanical-clock", "name": "Mechanical clock", "year": "1300 AD", "yearN": 1300, "zone": "post-classical", "domain": "economics", "constraint": "time as natural and approximate", "parents": 4, "children": 4, "url": "https://ticks.iamkesava.com/#/walk/mechanical-clock"}, {"id": "black-death-as-social-disruptor", "name": "Black Death as social disruptor", "year": "1347 AD", "yearN": 1347, "zone": "post-classical", "domain": "medicine", "constraint": "feudal labor relations (by killing a third of Europe)", "parents": 3, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/black-death-as-social-disruptor"}, {"id": "linear-perspective-brunelleschi", "name": "Linear perspective (Brunelleschi)", "year": "1415 AD", "yearN": 1415, "zone": "early-modern", "domain": "art", "constraint": "depicted space as symbolic and flat", "parents": 4, "children": 4, "url": "https://ticks.iamkesava.com/#/walk/linear-perspective-brunelleschi"}, {"id": "brunelleschis-dome-florence", "name": "Brunelleschi's dome (Florence)", "year": "1420 AD", "yearN": 1420, "zone": "early-modern", "domain": "art", "constraint": "large dome construction requiring wooden centering", "parents": 3, "children": 4, "url": "https://ticks.iamkesava.com/#/walk/brunelleschis-dome-florence"}, {"id": "gutenbergs-printing-press", "name": "Gutenberg's printing press", "year": "1440 AD", "yearN": 1440, "zone": "early-modern", "domain": "language", "constraint": "text reproduction requiring manual copying", "parents": 7, "children": 6, "url": "https://ticks.iamkesava.com/#/walk/gutenbergs-printing-press"}, {"id": "columbian-exchange", "name": "Columbian Exchange", "year": "1492 AD", "yearN": 1492, "zone": "early-modern", "domain": "agriculture", "constraint": "Old and New World as biologically separate", "parents": 4, "children": 3, "url": "https://ticks.iamkesava.com/#/walk/columbian-exchange"}, {"id": "ambroise-par-wound-treatment-reform", "name": "Ambroise Paré / wound treatment reform", "year": "1545 AD", "yearN": 1545, "zone": "early-modern", "domain": "medicine", "constraint": "gunshot wounds requiring boiling oil cauterization", "parents": 3, "children": 3, "url": "https://ticks.iamkesava.com/#/walk/ambroise-par-wound-treatment-reform"}, {"id": "copernican-heliocentrism", "name": "Copernican heliocentrism", "year": "1543 AD", "yearN": 1543, "zone": "early-modern", "domain": "philosophy", "constraint": "human civilization as the cosmic center", "parents": 4, "children": 5, "url": "https://ticks.iamkesava.com/#/walk/copernican-heliocentrism"}, {"id": "human-anatomy-vesalius", "name": "Human anatomy (Vesalius)", "year": "1543 AD", "yearN": 1543, "zone": "early-modern", "domain": "medicine", "constraint": "the body as known through Galen's ancient texts", "parents": 4, "children": 4, "url": "https://ticks.iamkesava.com/#/walk/human-anatomy-vesalius"}, {"id": "mercator-projection", "name": "Mercator projection", "year": "1569 AD", "yearN": 1569, "zone": "early-modern", "domain": "society", "constraint": "compass bearing requiring curved-surface math", "parents": 3, "children": 3, "url": "https://ticks.iamkesava.com/#/walk/mercator-projection"}, {"id": "dutch-east-india-company-first-joint-stock-co", "name": "Dutch East India Company (first joint-stock co.)", "year": "1602 AD", "yearN": 1602, "zone": "early-modern", "domain": "economics", "constraint": "large ventures limited by single investor's capital", "parents": 5, "children": 4, "url": "https://ticks.iamkesava.com/#/walk/dutch-east-india-company-first-joint-stock-co"}, {"id": "amsterdam-stock-exchange", "name": "Amsterdam Stock Exchange", "year": "1611 AD", "yearN": 1611, "zone": "early-modern", "domain": "economics", "constraint": "investment requiring direct relationship with issuer", "parents": 3, "children": 5, "url": "https://ticks.iamkesava.com/#/walk/amsterdam-stock-exchange"}, {"id": "compound-microscope", "name": "Compound microscope", "year": "1590 AD", "yearN": 1590, "zone": "early-modern", "domain": "medicine", "constraint": "the visible as the limit of the knowable", "parents": 2, "children": 5, "url": "https://ticks.iamkesava.com/#/walk/compound-microscope"}, {"id": "experimental-method-bacon", "name": "Experimental method (Bacon)", "year": "1620 AD", "yearN": 1620, "zone": "early-modern", "domain": "philosophy", "constraint": "knowledge 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"yearN": 1927, "zone": "electric-age", "domain": "biology", "constraint": "genetic mutation as a random, uncontrollable event", "parents": 9, "children": 6, "url": "https://ticks.iamkesava.com/#/walk/mutation-via-x-rays-muller"}, {"id": "dna-as-the-genetic-material-avery-et-al", "name": "DNA as the genetic material (Avery et al.)", "year": "1944 AD", "yearN": 1944, "zone": "electric-age", "domain": "biology", "constraint": "protein as the presumed carrier of genetic information", "parents": 5, "children": 5, "url": "https://ticks.iamkesava.com/#/walk/dna-as-the-genetic-material-avery-et-al"}, {"id": "genetic-code-protein-synthesis-cricks-central-dogma", "name": "Genetic code / protein synthesis (Crick's central dogma)", "year": "1953 AD", "yearN": 1953, "zone": "electric-age", "domain": "biology", "constraint": "the mechanism connecting DNA to protein as unknown", "parents": 3, "children": 5, "url": 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"human-genome-sequence-completed", "name": "Human genome sequence completed", "year": "2003 AD", "yearN": 2003, "zone": "network-age", "domain": "biology", "constraint": "the complete human genetic blueprint as unknown", "parents": 4, "children": 5, "url": "https://ticks.iamkesava.com/#/walk/human-genome-sequence-completed"}, {"id": "induced-pluripotent-stem-cells-yamanaka", "name": "Induced pluripotent stem cells (Yamanaka)", "year": "2006 AD", "yearN": 2006, "zone": "network-age", "domain": "biology", "constraint": "pluripotent stem cells requiring embryo destruction to obtain", "parents": 1, "children": 4, "url": "https://ticks.iamkesava.com/#/walk/induced-pluripotent-stem-cells-yamanaka"}, {"id": "crispr-cas9-as-genome-editing-tool-doudna-charpentier", "name": "CRISPR-Cas9 as genome editing tool (Doudna/Charpentier)", "year": "2012 AD", "yearN": 2012, "zone": "network-age", "domain": "biology", "constraint": "precise genome editing as requiring complex zinc finger or TALEN 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{"id": "freud-unconscious-as-causally-active", "name": "Freud / unconscious as causally active", "year": "1900 AD", "yearN": 1900, "zone": "electric-age", "domain": "mind", "constraint": "behavior as fully explicable by conscious intention", "parents": 3, "children": 3, "url": "https://ticks.iamkesava.com/#/walk/freud-unconscious-as-causally-active"}, {"id": "binet-simon-intelligence-test-iq", "name": "Binet-Simon intelligence test (IQ)", "year": "1905 AD", "yearN": 1905, "zone": "electric-age", "domain": "mind", "constraint": "cognitive ability as unmeasurable", "parents": 4, "children": 3, "url": "https://ticks.iamkesava.com/#/walk/binet-simon-intelligence-test-iq"}, {"id": "rorschach-inkblot-test", "name": "Rorschach inkblot test", "year": "1921 AD", "yearN": 1921, "zone": "electric-age", "domain": "mind", "constraint": "unconscious thought patterns as inaccessible to external observation", "parents": 3, "children": 4, "url": 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"mind", "constraint": "prison guard brutality as a selection effect (bad people becoming guards)", "parents": 3, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/stanford-prison-experiment"}, {"id": "tversky-and-kahneman-heuristics-and-biases", "name": "Tversky and Kahneman / heuristics and biases", "year": "1972 AD", "yearN": 1972, "zone": "space-digital", "domain": "mind", "constraint": "human judgment errors as random noise rather than systematic patterns", "parents": 3, "children": 5, "url": "https://ticks.iamkesava.com/#/walk/tversky-and-kahneman-heuristics-and-biases"}, {"id": "sociobiology-e-o-wilson", "name": "Sociobiology (E.O. 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"french-revolution-popular-sovereignty", "name": "French Revolution / popular sovereignty", "year": "1789 AD", "yearN": 1789, "zone": "industrial", "domain": "society", "constraint": "sovereignty as vested in the monarch", "parents": 4, "children": 1, "url": "https://ticks.iamkesava.com/#/walk/french-revolution-popular-sovereignty"}, {"id": "seneca-falls-convention-womens-rights-declaration", "name": "Seneca Falls Convention / women's rights declaration", "year": "1848 AD", "yearN": 1848, "zone": "industrial", "domain": "society", "constraint": "political claims-making as exclusively male", "parents": 6, "children": 3, "url": "https://ticks.iamkesava.com/#/walk/seneca-falls-convention-womens-rights-declaration"}, {"id": "emancipation-proclamation", "name": "Emancipation Proclamation", "year": "1863 AD", "yearN": 1863, "zone": "industrial", "domain": "society", "constraint": "racial chattel slavery as a permanent constitutional institution in the US", "parents": 11, "children": 7, 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{"id": "gilgamesh-epic-first-literary-theology", "name": "Gilgamesh Epic / first literary theology", "year": "2100 BC", "yearN": -2100, "zone": "first-civilizations", "domain": "religion", "constraint": "divine relationships as purely ritual and transactional", "parents": 5, "children": 4, "url": "https://ticks.iamkesava.com/#/walk/gilgamesh-epic-first-literary-theology"}, {"id": "zoroaster-cosmic-dualism", "name": "Zoroaster's teaching / cosmic dualism", "year": "600 BC", "yearN": -600, "zone": "axial-age", "domain": "religion", "constraint": "morality as tribal custom rather than cosmic struggle", "parents": 5, "children": 3, "url": "https://ticks.iamkesava.com/#/walk/zoroaster-cosmic-dualism"}, {"id": "jainism-radical-non-violence-ahimsa", "name": "Jainism / radical non-violence (ahimsa)", "year": "500 BC", "yearN": -500, "zone": "axial-age", "domain": "religion", "constraint": "religious merit as requiring ritual sacrifice or priestly mediation", "parents": 4, "children": 2, "url": 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"copernicus-religion-confronts-cosmology", "name": "Copernicus / religion confronts cosmology", "year": "1543 AD", "yearN": 1543, "zone": "early-modern", "domain": "religion", "constraint": "Earth's central position as theological necessity", "parents": 3, "children": 3, "url": "https://ticks.iamkesava.com/#/walk/copernicus-religion-confronts-cosmology"}, {"id": "galileos-trial-science-vs-institutional-religion", "name": "Galileo's trial / science vs. institutional religion", "year": "1633 AD", "yearN": 1633, "zone": "early-modern", "domain": "religion", "constraint": "natural philosophy as subordinate to theological authority", "parents": 4, "children": 3, "url": "https://ticks.iamkesava.com/#/walk/galileos-trial-science-vs-institutional-religion"}, {"id": "hobbes-leviathan-secular-political-theory", "name": "Hobbes' Leviathan / secular political theory", "year": "1651 AD", "yearN": 1651, "zone": "early-modern", "domain": "religion", "constraint": "political philosophy as requiring 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"domain": "philosophy", "constraint": "human nature as fixed and essence-giving", "parents": 2, "children": 6, "url": "https://ticks.iamkesava.com/#/walk/sartres-being-and-nothingness-radical-freedom"}, {"id": "vatican-ii-catholic-churchs-modernization", "name": "Vatican II / Catholic Church's modernization", "year": "1962 AD", "yearN": 1962, "zone": "space-digital", "domain": "religion", "constraint": "the Catholic Church's stance toward modernity as primarily hostile", "parents": 10, "children": 3, "url": "https://ticks.iamkesava.com/#/walk/vatican-ii-catholic-churchs-modernization"}, {"id": "rawls-theory-of-justice", "name": "Rawls' Theory of Justice", "year": "1971 AD", "yearN": 1971, "zone": "space-digital", "domain": "philosophy", "constraint": "political philosophy as either utilitarian or natural rights based", "parents": 2, "children": 7, "url": "https://ticks.iamkesava.com/#/walk/rawls-theory-of-justice"}, {"id": "singers-animal-liberation-effective-altruism-roots", "name": "Singer's Animal Liberation / effective altruism roots", "year": "1975 AD", "yearN": 1975, "zone": "space-digital", "domain": "philosophy", "constraint": "moral consideration as limited to humans", "parents": 4, "children": 4, "url": "https://ticks.iamkesava.com/#/walk/singers-animal-liberation-effective-altruism-roots"}, {"id": "rice-domestication-yangtze-valley", "name": "Rice domestication (Yangtze Valley)", "year": "7,000 BC", "yearN": -7000, "zone": "settled-world", "domain": "agriculture", "constraint": "East Asian food security as dependent on millet and tubers", "parents": 2, "children": 5, "url": "https://ticks.iamkesava.com/#/walk/rice-domestication-yangtze-valley"}, {"id": "plow-agriculture", "name": "Plow agriculture", "year": "3500 BC", "yearN": -3500, "zone": "settled-world", "domain": "agriculture", "constraint": "soil turning as requiring intensive human or hand labor", "parents": 4, "children": 4, "url": "https://ticks.iamkesava.com/#/walk/plow-agriculture"}, {"id": "three-field-crop-rotation-medieval-europe", "name": "Three-field crop rotation (Medieval Europe)", "year": "1000 AD", "yearN": 1000, "zone": "post-classical", "domain": "agriculture", "constraint": "annual soil exhaustion requiring fallow of 50% of arable land", "parents": 4, "children": 3, "url": "https://ticks.iamkesava.com/#/walk/three-field-crop-rotation-medieval-europe"}, {"id": "potato-introduction-to-europe", "name": "Potato introduction to Europe", "year": "1565 AD", "yearN": 1565, "zone": "early-modern", "domain": "agriculture", "constraint": "European caloric yield per acre as limited by grain crops", "parents": 4, "children": 4, "url": "https://ticks.iamkesava.com/#/walk/potato-introduction-to-europe"}, {"id": "maize-corn-global-spread", "name": "Maize / corn global spread", "year": "1500 AD", "yearN": 1500, "zone": "early-modern", "domain": "agriculture", "constraint": "African, Asian, and Southern European grain options as the only staple choices", "parents": 2, "children": 4, "url": "https://ticks.iamkesava.com/#/walk/maize-corn-global-spread"}, {"id": "chemical-fertilizer-liebigs-mineral-theory", "name": "Chemical fertilizer (Liebig's mineral theory)", "year": "1840 AD", "yearN": 1840, "zone": "industrial", "domain": "agriculture", "constraint": "soil fertility as a mystical property requiring organic matter", "parents": 8, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/chemical-fertilizer-liebigs-mineral-theory"}, {"id": "refrigeration-cold-chain", "name": "Refrigeration / cold chain", "year": "1870 AD", "yearN": 1870, "zone": "industrial", "domain": "agriculture", "constraint": "food distribution range limited by spoilage time", "parents": 9, "children": 4, "url": "https://ticks.iamkesava.com/#/walk/refrigeration-cold-chain"}, {"id": "pasteurization-of-milk", "name": "Pasteurization of milk", "year": "1900 AD", "yearN": 1900, "zone": "electric-age", "domain": "agriculture", "constraint": "milk as a vector for tuberculosis, 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"hayeks-road-to-serfdom-price-mechanism", "name": "Hayek's Road to Serfdom / price mechanism", "year": "1944 AD", "yearN": 1944, "zone": "electric-age", "domain": "economics", "constraint": "central planning as a viable alternative to markets for resource allocation", "parents": 2, "children": 5, "url": "https://ticks.iamkesava.com/#/walk/hayeks-road-to-serfdom-price-mechanism"}, {"id": "arrow-debreu-model-general-equilibrium", "name": "Arrow-Debreu model / general equilibrium", "year": "1954 AD", "yearN": 1954, "zone": "electric-age", "domain": "economics", "constraint": "competitive markets' efficiency as an empirical claim rather than proved theorem", "parents": 5, "children": 7, "url": "https://ticks.iamkesava.com/#/walk/arrow-debreu-model-general-equilibrium"}, {"id": "phillips-curve-inflation-unemployment-tradeoff", "name": "Phillips curve / inflation-unemployment tradeoff", "year": "1958 AD", "yearN": 1958, "zone": "electric-age", "domain": "economics", "constraint": "inflation 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"surrealism-manifesto-breton", "name": "Surrealism manifesto (Breton)", "year": "1924 AD", "yearN": 1924, "zone": "electric-age", "domain": "art", "constraint": "art as subject to rational control and conscious intention", "parents": 2, "children": 3, "url": "https://ticks.iamkesava.com/#/walk/surrealism-manifesto-breton"}, {"id": "abstract-expressionism-new-york-becomes-art-capital", "name": "Abstract Expressionism / New York becomes art capital", "year": "1947 AD", "yearN": 1947, "zone": "electric-age", "domain": "art", "constraint": "European cities as the exclusive centers of contemporary art", "parents": 4, "children": 3, "url": "https://ticks.iamkesava.com/#/walk/abstract-expressionism-new-york-becomes-art-capital"}, {"id": "pop-art-warhols-campbells-soup-cans", "name": "Pop Art / Warhol's Campbell's Soup Cans", "year": "1962 AD", "yearN": 1962, "zone": "space-digital", "domain": "art", "constraint": "the distinction between high art and commercial imagery", "parents": 6, 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"eniac-first-general-purpose-electronic-computer", "name": "ENIAC / first general-purpose electronic computer", "year": "1946 AD", "yearN": 1946, "zone": "electric-age", "domain": "computing", "constraint": "programmable computation as requiring mechanical or electromechanical components", "parents": 2, "children": 3, "url": "https://ticks.iamkesava.com/#/walk/eniac-first-general-purpose-electronic-computer"}, {"id": "transistor-bell-labs-shockley-bardeen-brattain", "name": "Transistor (Bell Labs, Shockley/Bardeen/Brattain)", "year": "1948 AD", "yearN": 1948, "zone": "electric-age", "domain": "computing", "constraint": "electronic switching requiring fragile, hot, power-hungry vacuum tubes", "parents": 3, "children": 4, "url": "https://ticks.iamkesava.com/#/walk/transistor-bell-labs-shockley-bardeen-brattain"}, {"id": "fortran-first-high-level-programming-language", "name": "FORTRAN / first high-level programming language", "year": "1957 AD", "yearN": 1957, "zone": "electric-age", 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"yearN": 1990, "zone": "space-digital", "domain": "computing", "constraint": "internet as requiring technical knowledge to navigate", "parents": 2, "children": 6, "url": "https://ticks.iamkesava.com/#/walk/world-wide-web-berners-lee-protocols"}, {"id": "javascript-browser-programming", "name": "JavaScript / browser programming", "year": "1995 AD", "yearN": 1995, "zone": "network-age", "domain": "computing", "constraint": "web pages as static documents that only servers could change", "parents": 3, "children": 3, "url": "https://ticks.iamkesava.com/#/walk/javascript-browser-programming"}, {"id": "facebooks-news-feed-algorithmic-social-curation", "name": "Facebook's News Feed / algorithmic social curation", "year": "2006 AD", "yearN": 2006, "zone": "network-age", "domain": "computing", "constraint": "social media feeds as chronological and user-curated", "parents": 3, "children": 4, "url": "https://ticks.iamkesava.com/#/walk/facebooks-news-feed-algorithmic-social-curation"}, {"id": "github-distributed-version-control", "name": "GitHub / distributed version control", "year": "2008 AD", "yearN": 2008, "zone": "network-age", "domain": "computing", "constraint": "collaborative software development requiring a central authoritative server", "parents": 2, "children": 5, "url": "https://ticks.iamkesava.com/#/walk/github-distributed-version-control"}, {"id": "kubernetes-container-orchestration", "name": "Kubernetes / container orchestration", "year": "2014 AD", "yearN": 2014, "zone": "network-age", "domain": "computing", "constraint": "cloud application deployment as requiring custom infrastructure configuration", "parents": 2, "children": 3, "url": "https://ticks.iamkesava.com/#/walk/kubernetes-container-orchestration"}, {"id": "gregorian-calendar-reform", "name": "Gregorian calendar reform", "year": "1582 AD", "yearN": 1582, "zone": "early-modern", "domain": "society", "constraint": "calendar drift from solar year accumulating to 10+ days", "parents": 6, "children": 4, 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{"id": "hannibal-crosses-the-alps-strategic-surprise", "name": "Hannibal crosses the Alps / strategic surprise", "year": "218 BC", "yearN": -218, "zone": "axial-age", "domain": "war", "constraint": "Alpine mountain ranges as an impassable barrier to military movement", "parents": 3, "children": 4, "url": "https://ticks.iamkesava.com/#/walk/hannibal-crosses-the-alps-strategic-surprise"}, {"id": "caesars-gallic-wars-total-conquest-doctrine", "name": "Caesar's Gallic Wars / total conquest doctrine", "year": "52 BC", "yearN": -52, "zone": "classical-empires", "domain": "war", "constraint": "conquest as requiring the submission of ruling elites only", "parents": 3, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/caesars-gallic-wars-total-conquest-doctrine"}, {"id": "battle-of-teutoburg-forest-limits-of-roman-expansion", "name": "Battle of Teutoburg Forest / limits of Roman expansion", "year": "9 AD", "yearN": 9, "zone": "classical-empires", "domain": "war", "constraint": "Roman 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{"id": "covid-pandemic-remote-work-as-default", "name": "COVID pandemic / remote work as default", "year": "2020 AD", "yearN": 2020, "zone": "ai-era", "domain": "economics", "constraint": "knowledge work as requiring physical co-location in offices", "parents": 8, "children": 1, "url": "https://ticks.iamkesava.com/#/walk/covid-pandemic-remote-work-as-default"}, {"id": "avicennas-floating-man-pure-self-awareness", "name": "Avicenna's floating man / pure self-awareness", "year": "1040 AD", "yearN": 1040, "zone": "post-classical", "domain": "philosophy", "constraint": "self-knowledge as requiring sensory or bodily experience", "parents": 3, "children": 6, "url": "https://ticks.iamkesava.com/#/walk/avicennas-floating-man-pure-self-awareness"}, {"id": "aquinas-synthesis-faith-and-reason", "name": "Aquinas' synthesis / faith and reason", "year": "1270 AD", "yearN": 1270, "zone": "post-classical", "domain": "philosophy", "constraint": "Christian theology and Aristotelian philosophy as 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"Kierkegaard / existential anxiety and choice", "year": "1843 AD", "yearN": 1843, "zone": "industrial", "domain": "philosophy", "constraint": "philosophy as addressing universal reason rather than individual existence", "parents": 6, "children": 5, "url": "https://ticks.iamkesava.com/#/walk/kierkegaard-existential-anxiety-and-choice"}, {"id": "mills-on-the-subjection-of-women", "name": "Mill's On the Subjection of Women", "year": "1869 AD", "yearN": 1869, "zone": "industrial", "domain": "philosophy", "constraint": "women's legal and social inequality as natural or inevitable", "parents": 3, "children": 5, "url": "https://ticks.iamkesava.com/#/walk/mills-on-the-subjection-of-women"}, {"id": "logical-positivism-vienna-circle", "name": "Logical positivism / Vienna Circle", "year": "1936 AD", "yearN": 1936, "zone": "electric-age", "domain": "philosophy", "constraint": "metaphysics as a legitimate philosophical enterprise", "parents": 2, "children": 5, "url": "https://ticks.iamkesava.com/#/walk/logical-positivism-vienna-circle"}, {"id": "poppers-falsificationism-philosophy-of-science", "name": "Popper's falsificationism / philosophy of science", "year": "1934 AD", "yearN": 1934, "zone": "electric-age", "domain": "philosophy", "constraint": "scientific theories as verified by confirming evidence", "parents": 3, "children": 3, "url": "https://ticks.iamkesava.com/#/walk/poppers-falsificationism-philosophy-of-science"}, {"id": "kuhns-structure-of-scientific-revolutions", "name": "Kuhn's Structure of Scientific Revolutions", "year": "1962 AD", "yearN": 1962, "zone": "space-digital", "domain": "philosophy", "constraint": "science as cumulative progress toward truth", "parents": 2, "children": 5, "url": "https://ticks.iamkesava.com/#/walk/kuhns-structure-of-scientific-revolutions"}, {"id": "derridas-deconstruction-of-grammatology", "name": "Derrida's deconstruction / Of Grammatology", "year": "1967 AD", "yearN": 1967, "zone": "space-digital", "domain": "philosophy", "constraint": "texts as having determinate, author-intended meanings", "parents": 3, "children": 5, "url": "https://ticks.iamkesava.com/#/walk/derridas-deconstruction-of-grammatology"}, {"id": "foucaults-discipline-and-punish-power-knowledge", "name": "Foucault's Discipline and Punish / power-knowledge", "year": "1975 AD", "yearN": 1975, "zone": "space-digital", "domain": "philosophy", "constraint": "power as primarily coercive and authority as primarily legitimate", "parents": 3, "children": 6, "url": "https://ticks.iamkesava.com/#/walk/foucaults-discipline-and-punish-power-knowledge"}, {"id": "singers-practical-ethics-applied-ethics-movement", "name": "Singer's practical ethics / applied ethics movement", "year": "1979 AD", "yearN": 1979, "zone": "space-digital", "domain": "philosophy", "constraint": "ethics as a purely theoretical enterprise with no implications for action", "parents": 2, "children": 5, "url": 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"https://ticks.iamkesava.com/#/walk/miller-urey-experiment-origin-of-life-chemistry"}, {"id": "leakeys-olduvai-gorge-discoveries-human-origins-in-africa", "name": "Leakey's Olduvai Gorge discoveries / human origins in Africa", "year": "1959 AD", "yearN": 1959, "zone": "electric-age", "domain": "biology", "constraint": "human evolutionary origin as undiscovered or Eurasian", "parents": 9, "children": 8, "url": "https://ticks.iamkesava.com/#/walk/leakeys-olduvai-gorge-discoveries-human-origins-in-africa"}, {"id": "synthetic-organic-chemistry-total-synthesis", "name": "Synthetic organic chemistry / total synthesis", "year": "1970 AD", "yearN": 1970, "zone": "space-digital", "domain": "physics", "constraint": "complex natural molecules as obtainable only by extraction from biological sources", "parents": 3, "children": 6, "url": "https://ticks.iamkesava.com/#/walk/synthetic-organic-chemistry-total-synthesis"}, {"id": "polymerase-chain-reaction-pcr-widespread-use", "name": "Polymerase chain 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"url": "https://ticks.iamkesava.com/#/walk/higgs-boson-discovery-standard-model-complete"}, {"id": "ligo-gravitational-wave-astronomy-opens", "name": "LIGO / gravitational wave astronomy opens", "year": "2015 AD", "yearN": 2015, "zone": "network-age", "domain": "physics", "constraint": "gravitational waves as detectable only in principle, not practice", "parents": 3, "children": 5, "url": "https://ticks.iamkesava.com/#/walk/ligo-gravitational-wave-astronomy-opens"}, {"id": "minoan-fresco-naturalistic-art", "name": "Minoan fresco / naturalistic art", "year": "1440 BC", "yearN": -1440, "zone": "first-civilizations", "domain": "art", "constraint": "artistic representation as symbolic and hierarchical rather than naturalistic", "parents": 4, "children": 5, "url": "https://ticks.iamkesava.com/#/walk/minoan-fresco-naturalistic-art"}, {"id": "greek-tragedy-public-emotional-catharsis", "name": "Greek tragedy / public emotional catharsis", "year": "470 BC", "yearN": -470, "zone": "axial-age", "domain": "art", "constraint": "suffering as private and shameful rather than publicly shareable", "parents": 9, "children": 3, "url": "https://ticks.iamkesava.com/#/walk/greek-tragedy-public-emotional-catharsis"}, {"id": "vasaris-lives-of-the-artists-art-history-invented", "name": "Vasari's Lives of the Artists / art history invented", "year": "1550 AD", "yearN": 1550, "zone": "early-modern", "domain": "art", "constraint": "artistic achievement as anonymous and transhistorical", "parents": 3, "children": 4, "url": "https://ticks.iamkesava.com/#/walk/vasaris-lives-of-the-artists-art-history-invented"}, {"id": "monteverdis-lorfeo-opera-invented", "name": "Monteverdi's L'Orfeo / opera invented", "year": "1607 AD", "yearN": 1607, "zone": "early-modern", "domain": "art", "constraint": "music drama as purely liturgical or instrumentally accompanied song", "parents": 2, "children": 4, "url": "https://ticks.iamkesava.com/#/walk/monteverdis-lorfeo-opera-invented"}, {"id": "photography-liberates-painting-impressionism", "name": "Photography liberates painting / Impressionism", "year": "1863 AD", "yearN": 1863, "zone": "industrial", "domain": "art", "constraint": "painting's primary function as faithful visual documentation", "parents": 2, "children": 3, "url": "https://ticks.iamkesava.com/#/walk/photography-liberates-painting-impressionism"}, {"id": "futurism-manifesto-art-as-technological-celebration", "name": "Futurism manifesto / art as technological celebration", "year": "1909 AD", "yearN": 1909, "zone": "electric-age", "domain": "art", "constraint": "art as oriented toward classical tradition and natural beauty", "parents": 3, "children": 5, "url": "https://ticks.iamkesava.com/#/walk/futurism-manifesto-art-as-technological-celebration"}, {"id": "de-stijl-geometric-abstraction", "name": "De Stijl / geometric abstraction", "year": "1917 AD", "yearN": 1917, "zone": "electric-age", "domain": "art", "constraint": "art as representing anything from 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"MTV / music video as art form", "year": "1981 AD", "yearN": 1981, "zone": "space-digital", "domain": "art", "constraint": "music as purely auditory — divorced from visual presentation", "parents": 2, "children": 4, "url": "https://ticks.iamkesava.com/#/walk/mtv-music-video-as-art-form"}, {"id": "world-wide-web-digital-art-and-net-art", "name": "World Wide Web / digital art and net art", "year": "1993 AD", "yearN": 1993, "zone": "space-digital", "domain": "art", "constraint": "art exhibition as requiring physical gallery presence", "parents": 3, "children": 7, "url": "https://ticks.iamkesava.com/#/walk/world-wide-web-digital-art-and-net-art"}, {"id": "social-stratification-first-hierarchies", "name": "Social stratification / first hierarchies", "year": "5000 BC", "yearN": -5000, "zone": "settled-world", "domain": "society", "constraint": "social equality as the default condition of human groups", "parents": 4, "children": 4, "url": 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"classical-empires", "domain": "society", "constraint": "the Roman state's right to require religious uniformity", "parents": 4, "children": 3, "url": "https://ticks.iamkesava.com/#/walk/edict-of-milan-religious-tolerance-as-policy"}, {"id": "brunelleschis-florence-urban-planning-as-art", "name": "Brunelleschi's Florence / urban planning as art", "year": "1436 AD", "yearN": 1436, "zone": "early-modern", "domain": "society", "constraint": "cities as organic growths without designed public spaces", "parents": 7, "children": 3, "url": "https://ticks.iamkesava.com/#/walk/brunelleschis-florence-urban-planning-as-art"}, {"id": "encyclop-die-diderot-dalembert-organized-human-knowledge", "name": "Encyclopédie (Diderot/d'Alembert) / organized human knowledge", "year": "1750 AD", "yearN": 1750, "zone": "early-modern", "domain": "society", "constraint": "knowledge as the property of guilds, churches, and aristocracy", "parents": 7, "children": 3, "url": 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1851, "zone": "industrial", "domain": "society", "constraint": "industrial production as nationally bounded and mutually opaque", "parents": 3, "children": 3, "url": "https://ticks.iamkesava.com/#/walk/great-exhibition-international-commerce-spectacle"}, {"id": "international-red-cross-transnational-humanitarianism", "name": "International Red Cross / transnational humanitarianism", "year": "1863 AD", "yearN": 1863, "zone": "industrial", "domain": "society", "constraint": "humanitarian action as bounded by national or religious affiliation", "parents": 3, "children": 1, "url": "https://ticks.iamkesava.com/#/walk/international-red-cross-transnational-humanitarianism"}, {"id": "settlement-house-movement-social-work-profession", "name": "Settlement house movement / social work profession", "year": "1889 AD", "yearN": 1889, "zone": "industrial", "domain": "society", "constraint": "poverty as a moral failing requiring charity rather than structural intervention", "parents": 6, "children": 3, "url": "https://ticks.iamkesava.com/#/walk/settlement-house-movement-social-work-profession"}, {"id": "freud-psychoanalysis-and-modern-selfhood", "name": "Freud / psychoanalysis and modern selfhood", "year": "1900 AD", "yearN": 1900, "zone": "electric-age", "domain": "society", "constraint": "the self as a unified, transparent, rational entity", "parents": 4, "children": 3, "url": "https://ticks.iamkesava.com/#/walk/freud-psychoanalysis-and-modern-selfhood"}, {"id": "san-francisco-earthquake-disaster-management", "name": "San Francisco earthquake / disaster management", "year": "1906 AD", "yearN": 1906, "zone": "electric-age", "domain": "society", "constraint": "large-scale urban disaster as manageable only by local resources", "parents": 3, "children": 4, "url": "https://ticks.iamkesava.com/#/walk/san-francisco-earthquake-disaster-management"}, {"id": "prohibition-moral-legislation-and-unintended-consequences", "name": "Prohibition / moral legislation and unintended consequences", "year": "1920 AD", "yearN": 1920, "zone": "electric-age", "domain": "society", "constraint": "alcohol as a legal commodity in the United States", "parents": 3, "children": 1, "url": "https://ticks.iamkesava.com/#/walk/prohibition-moral-legislation-and-unintended-consequences"}, {"id": "social-security-act-welfare-state-established-us", "name": "Social Security Act / welfare state established (US)", "year": "1935 AD", "yearN": 1935, "zone": "electric-age", "domain": "society", "constraint": "old-age poverty as an individual's private problem", "parents": 6, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/social-security-act-welfare-state-established-us"}, {"id": "state-of-israel-established-jewish-homeland", "name": "State of Israel established / Jewish homeland", "year": "1948 AD", "yearN": 1948, "zone": "electric-age", "domain": "society", "constraint": "Jewish statelessness as a permanent condition after 2000 years of diaspora", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/state-of-israel-established-jewish-homeland"}, {"id": "rosa-parks-montgomery-bus-boycott", "name": "Rosa Parks / Montgomery Bus Boycott", "year": "1955 AD", "yearN": 1955, "zone": "electric-age", "domain": "society", "constraint": "racial bus segregation as an immovable social fact in Montgomery, Alabama", "parents": 4, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/rosa-parks-montgomery-bus-boycott"}, {"id": "stonewall-inn-riots-gay-liberation", "name": "Stonewall Inn riots / gay liberation", "year": "1969 AD", "yearN": 1969, "zone": "space-digital", "domain": "society", "constraint": "homosexuality as criminal and requiring closeted existence", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/stonewall-inn-riots-gay-liberation"}, {"id": "title-ix-womens-sports-equality", "name": "Title IX / women's sports equality", "year": "1972 AD", "yearN": 1972, "zone": "space-digital", "domain": "society", "constraint": 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"george-floyd-murder-global-racial-justice-reckoning", "name": "George Floyd murder / global racial justice reckoning", "year": "2020 AD", "yearN": 2020, "zone": "ai-era", "domain": "society", "constraint": "police violence against Black Americans as a local or regional concern", "parents": 3, "children": 0, "url": "https://ticks.iamkesava.com/#/walk/george-floyd-murder-global-racial-justice-reckoning"}, {"id": "siege-warfare-formalized-assyrian", "name": "Siege warfare formalized (Assyrian)", "year": "700 BC", "yearN": -700, "zone": "axial-age", "domain": "war", "constraint": "fortified cities as effectively unconquerable", "parents": 3, "children": 6, "url": "https://ticks.iamkesava.com/#/walk/siege-warfare-formalized-assyrian"}, {"id": "pyrrhic-victory-cost-of-tactical-success", "name": "Pyrrhic victory / cost of tactical success", "year": "280 BC", "yearN": -280, "zone": "axial-age", "domain": "war", "constraint": "tactical victory as equivalent to strategic success", "parents": 3, "children": 4, "url": "https://ticks.iamkesava.com/#/walk/pyrrhic-victory-cost-of-tactical-success"}, {"id": "genghis-khans-yam-military-communications", "name": "Genghis Khan's Yam / military communications", "year": "1200 AD", "yearN": 1200, "zone": "post-classical", "domain": "war", "constraint": "army command requiring the general's physical proximity", "parents": 3, "children": 5, "url": "https://ticks.iamkesava.com/#/walk/genghis-khans-yam-military-communications"}, {"id": "musket-warfare-drill-and-volley-fire", "name": "Musket warfare / drill and volley fire", "year": "1599 AD", "yearN": 1599, "zone": "early-modern", "domain": "war", "constraint": "firearms as individual weapons requiring slow reload before each shot", "parents": 2, "children": 5, "url": "https://ticks.iamkesava.com/#/walk/musket-warfare-drill-and-volley-fire"}, {"id": "battle-of-quebec-amphibious-operational-art", "name": "Battle of Quebec / amphibious operational art", "year": "1759 AD", "yearN": 1759, "zone": "early-modern", "domain": "war", "constraint": "inland fortified cities as protected from seaborne assault", "parents": 5, "children": 4, "url": "https://ticks.iamkesava.com/#/walk/battle-of-quebec-amphibious-operational-art"}, {"id": "napoleons-egyptian-campaign-intelligence-failure", "name": "Napoleon's Egyptian campaign / intelligence failure", "year": "1798 AD", "yearN": 1798, "zone": "industrial", "domain": "war", "constraint": "strategic surprise as achievable regardless of naval inferiority", "parents": 2, "children": 4, "url": "https://ticks.iamkesava.com/#/walk/napoleons-egyptian-campaign-intelligence-failure"}, {"id": "rifled-musket-accurate-infantry-fire", "name": "Rifled musket / accurate infantry fire", "year": "1855 AD", "yearN": 1855, "zone": "industrial", "domain": "war", "constraint": "infantry combat accuracy beyond 50-100 yards", "parents": 6, "children": 4, "url": "https://ticks.iamkesava.com/#/walk/rifled-musket-accurate-infantry-fire"}, {"id": "telegraph-in-warfare-real-time-command", "name": "Telegraph in warfare / real-time command", "year": "1862 AD", "yearN": 1862, "zone": "industrial", "domain": "war", "constraint": "battlefield command requiring physical messenger or visual signal", "parents": 1, "children": 6, "url": "https://ticks.iamkesava.com/#/walk/telegraph-in-warfare-real-time-command"}, {"id": "poison-gas-at-ypres-chemical-weapons", "name": "Poison gas at Ypres / chemical weapons", "year": "1915 AD", "yearN": 1915, "zone": "electric-age", "domain": "war", "constraint": "warfare as constrained to kinetic weapons", "parents": 1, "children": 4, "url": "https://ticks.iamkesava.com/#/walk/poison-gas-at-ypres-chemical-weapons"}, {"id": "operation-overlord-deception-information-warfare", "name": "Operation Overlord deception / information warfare", "year": "1944 AD", "yearN": 1944, "zone": "electric-age", "domain": "war", "constraint": "military deception as limited to local tactical feints", "parents": 1, "children": 4, "url": "https://ticks.iamkesava.com/#/walk/operation-overlord-deception-information-warfare"}, {"id": "korean-war-limited-war-doctrine", "name": "Korean War / limited war doctrine", "year": "1950 AD", "yearN": 1950, "zone": "electric-age", "domain": "war", "constraint": "victory as the only acceptable outcome of great-power military engagement", "parents": 3, "children": 6, "url": "https://ticks.iamkesava.com/#/walk/korean-war-limited-war-doctrine"}, {"id": "six-day-war-preemptive-strike-doctrine", "name": "Six-Day War / preemptive strike doctrine", "year": "1967 AD", "yearN": 1967, "zone": "space-digital", "domain": "war", "constraint": "strategic advantage as requiring absorbing the first blow", "parents": 8, "children": 3, "url": "https://ticks.iamkesava.com/#/walk/six-day-war-preemptive-strike-doctrine"}, {"id": "stealth-technology-radar-invisibility", "name": "Stealth technology / radar invisibility", "year": "1991 AD", "yearN": 1991, "zone": "space-digital", "domain": "war", "constraint": "aircraft visibility to radar as inherent to any flying object", "parents": 3, "children": 3, "url": "https://ticks.iamkesava.com/#/walk/stealth-technology-radar-invisibility"}, {"id": "islamic-state-social-media-terrorist-recruitment", "name": "Islamic State / social media terrorist recruitment", "year": "2014 AD", "yearN": 2014, "zone": "network-age", "domain": "war", "constraint": "terrorist recruitment as requiring personal networks and physical contact", "parents": 6, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/islamic-state-social-media-terrorist-recruitment"}, {"id": "abo-blood-typing-transfusion-medicine", "name": "ABO blood typing / transfusion medicine", "year": "1900 AD", "yearN": 1900, "zone": "electric-age", "domain": "biology", "constraint": "blood transfusion as unpredictably fatal due to unknown compatibility", "parents": 3, "children": 6, "url": "https://ticks.iamkesava.com/#/walk/abo-blood-typing-transfusion-medicine"}, {"id": "rh-factor-discovery-landsteiner-wiener", "name": "Rh factor discovery (Landsteiner/Wiener)", "year": "1940 AD", "yearN": 1940, "zone": "electric-age", "domain": "biology", "constraint": "blood compatibility as fully explained by ABO typing", "parents": 10, "children": 5, "url": "https://ticks.iamkesava.com/#/walk/rh-factor-discovery-landsteiner-wiener"}, {"id": "antibiotic-resistance-first-observed-penicillin", "name": "Antibiotic resistance first observed (penicillin)", "year": "1950 AD", "yearN": 1950, "zone": "electric-age", "domain": "biology", "constraint": "antibiotics as permanently effective against susceptible bacteria", "parents": 6, "children": 5, "url": "https://ticks.iamkesava.com/#/walk/antibiotic-resistance-first-observed-penicillin"}, {"id": "thalidomide-disaster-drug-safety-regulation", "name": "Thalidomide disaster / drug safety regulation", "year": "1961 AD", "yearN": 1961, "zone": "space-digital", "domain": "biology", "constraint": "pharmaceutical approval as based 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"husserls-phenomenology", "name": "Husserl's phenomenology", "year": "1900 AD", "yearN": 1900, "zone": "electric-age", "domain": "philosophy", "constraint": "consciousness as transparent to introspection", "parents": 3, "children": 4, "url": "https://ticks.iamkesava.com/#/walk/husserls-phenomenology"}, {"id": "wittgensteins-tractatus-logical-atomism", "name": "Wittgenstein's Tractatus / logical atomism", "year": "1921 AD", "yearN": 1921, "zone": "electric-age", "domain": "philosophy", "constraint": "philosophy as capable of solving all meaningful questions", "parents": 2, "children": 4, "url": "https://ticks.iamkesava.com/#/walk/wittgensteins-tractatus-logical-atomism"}, {"id": "philosophical-investigations-wittgenstein", "name": "Philosophical Investigations (Wittgenstein)", "year": "1953 AD", "yearN": 1953, "zone": "electric-age", "domain": "philosophy", "constraint": "meaning as a property of words independent of use", "parents": 4, "children": 5, "url": 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"dartmouth-workshop-ai-as-a-field", "name": "Dartmouth Workshop / AI as a field", "year": "1956 AD", "yearN": 1956, "zone": "electric-age", "domain": "mind", "constraint": "machine intelligence as science fiction rather than research program", "parents": 3, "children": 7, "url": "https://ticks.iamkesava.com/#/walk/dartmouth-workshop-ai-as-a-field"}, {"id": "cognitive-dissonance-theory-festinger", "name": "Cognitive dissonance theory (Festinger)", "year": "1957 AD", "yearN": 1957, "zone": "electric-age", "domain": "mind", "constraint": "behavior as driven by rational assessment of evidence", "parents": 3, "children": 3, "url": "https://ticks.iamkesava.com/#/walk/cognitive-dissonance-theory-festinger"}, {"id": "terror-management-theory-becker-greenberg", "name": "Terror Management Theory (Becker/Greenberg)", "year": "1986 AD", "yearN": 1986, "zone": "space-digital", "domain": "mind", "constraint": "culture as merely adaptive or aesthetically motivated", "parents": 2, "children": 4, 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"opec-oil-embargo-and-price-shock", "name": "OPEC oil embargo and price shock", "year": "1973 AD", "yearN": 1973, "zone": "space-digital", "domain": "economics", "constraint": "energy prices as determined by consuming-nation governments", "parents": 2, "children": 5, "url": "https://ticks.iamkesava.com/#/walk/opec-oil-embargo-and-price-shock"}, {"id": "401-k-defined-contribution-retirement", "name": "401(k) defined contribution retirement", "year": "1978 AD", "yearN": 1978, "zone": "space-digital", "domain": "economics", "constraint": "retirement security requiring employer pension or government provision", "parents": 6, "children": 4, "url": "https://ticks.iamkesava.com/#/walk/401-k-defined-contribution-retirement"}, {"id": "iphone-app-store-platform-economy", "name": "iPhone App Store / platform economy", "year": "2008 AD", "yearN": 2008, "zone": "network-age", "domain": "economics", "constraint": "software distribution requiring physical retail or direct download", "parents": 3, 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"photography-frees-painting-from-representation", "name": "Photography frees painting from representation", "year": "1839 AD", "yearN": 1839, "zone": "industrial", "domain": "art", "constraint": "art's prestige dependent on verisimilitude", "parents": 3, "children": 3, "url": "https://ticks.iamkesava.com/#/walk/photography-frees-painting-from-representation"}, {"id": "rite-of-spring-premiere-modernism-in-music", "name": "Rite of Spring premiere / modernism in music", "year": "1913 AD", "yearN": 1913, "zone": "electric-age", "domain": "art", "constraint": "Western harmony as the necessary basis for serious music", "parents": 1, "children": 3, "url": "https://ticks.iamkesava.com/#/walk/rite-of-spring-premiere-modernism-in-music"}, {"id": "the-jazz-singer-sound-film", "name": "The Jazz Singer / sound film", "year": "1927 AD", "yearN": 1927, "zone": "electric-age", "domain": "art", "constraint": "cinema as a silent visual medium", "parents": 2, "children": 4, "url": 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"diplomatic-correspondence-in-italian-lingua-franca", "name": "Diplomatic correspondence in Italian (lingua franca)", "year": "1600 AD", "yearN": 1600, "zone": "early-modern", "domain": "language", "constraint": "diplomacy requiring Latin fluency", "parents": 3, "children": 6, "url": "https://ticks.iamkesava.com/#/walk/diplomatic-correspondence-in-italian-lingua-franca"}, {"id": "champollion-deciphers-hieroglyphics-rosetta-stone", "name": "Champollion deciphers hieroglyphics (Rosetta Stone)", "year": "1822 AD", "yearN": 1822, "zone": "industrial", "domain": "language", "constraint": "ancient Egyptian writing as permanently unreadable", "parents": 4, "children": 9, "url": "https://ticks.iamkesava.com/#/walk/champollion-deciphers-hieroglyphics-rosetta-stone"}, {"id": "braille-system-standardized", "name": "Braille system standardized", "year": "1837 AD", "yearN": 1837, "zone": "industrial", "domain": "language", "constraint": "written communication inaccessible to people without sight", 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"industrial", "domain": "society", "constraint": "humanitarian aid to war victims requiring government authorization", "parents": 2, "children": 4, "url": "https://ticks.iamkesava.com/#/walk/red-cross-founded-dunants-solferino"}, {"id": "bretton-woods-institutions-global-economic-governance", "name": "Bretton Woods institutions / global economic governance", "year": "1944 AD", "yearN": 1944, "zone": "electric-age", "domain": "society", "constraint": "international economic crises as having no institutional response mechanism", "parents": 1, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/bretton-woods-institutions-global-economic-governance"}, {"id": "opec-founded-resource-nationalism", "name": "OPEC founded / resource nationalism", "year": "1960 AD", "yearN": 1960, "zone": "space-digital", "domain": "society", "constraint": "oil pricing as controlled by Western international companies", "parents": 2, "children": 3, "url": 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"axial-age", "domain": "economics", "constraint": "state control requiring armies to be physically present", "parents": 4, "children": 3, "url": "https://ticks.iamkesava.com/#/walk/persian-royal-road-communications-infrastructure"}, {"id": "phoenician-purple-dye-luxury-trade", "name": "Phoenician purple dye / luxury trade", "year": "1200 BC", "yearN": -1200, "zone": "first-civilizations", "domain": "economics", "constraint": "rare color as occurring only in nature and uncapturable at scale", "parents": 2, "children": 4, "url": "https://ticks.iamkesava.com/#/walk/phoenician-purple-dye-luxury-trade"}, {"id": "us-constitution-written-fundamental-law", "name": "US Constitution / written fundamental law", "year": "1787 AD", "yearN": 1787, "zone": "industrial", "domain": "law", "constraint": "constitutional principles as unwritten conventions", "parents": 2, "children": 3, "url": "https://ticks.iamkesava.com/#/walk/us-constitution-written-fundamental-law"}, {"id": "metropolitan-police-professional-police-force", "name": "Metropolitan Police / professional police force", "year": "1829 AD", "yearN": 1829, "zone": "industrial", "domain": "law", "constraint": "public order maintained only by military or private means", "parents": 6, "children": 5, "url": "https://ticks.iamkesava.com/#/walk/metropolitan-police-professional-police-force"}, {"id": "marshall-plan-development-aid-as-strategy", "name": "Marshall Plan / development aid as strategy", "year": "1947 AD", "yearN": 1947, "zone": "electric-age", "domain": "economics", "constraint": "postwar reconstruction as a domestic political impossibility for defeated powers", "parents": 4, "children": 5, "url": "https://ticks.iamkesava.com/#/walk/marshall-plan-development-aid-as-strategy"}, {"id": "treaty-of-rome-european-integration", "name": "Treaty of Rome / European integration", "year": "1957 AD", "yearN": 1957, "zone": "electric-age", "domain": "law", "constraint": "European peace requiring American 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Virginia)", "year": "1967 AD", "yearN": 1967, "zone": "space-digital", "domain": "law", "constraint": "marriage law as a legitimate tool of racial separation", "parents": 3, "children": 3, "url": "https://ticks.iamkesava.com/#/walk/interracial-marriage-legalized-loving-v-virginia"}, {"id": "lawrence-v-texas-sodomy-laws-struck-down", "name": "Lawrence v. 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"https://ticks.iamkesava.com/#/walk/cd-rom-digital-storage-for-audio"}, {"id": "napster-peer-to-peer-file-sharing", "name": "Napster / peer-to-peer file sharing", "year": "1999 AD", "yearN": 1999, "zone": "network-age", "domain": "computing", "constraint": "digital content distribution requiring server infrastructure", "parents": 5, "children": 5, "url": "https://ticks.iamkesava.com/#/walk/napster-peer-to-peer-file-sharing"}, {"id": "bayh-dole-act-university-patent-rights", "name": "Bayh-Dole Act / university patent rights", "year": "1980 AD", "yearN": 1980, "zone": "space-digital", "domain": "law", "constraint": "federally funded research as non-commercializable", "parents": 6, "children": 4, "url": "https://ticks.iamkesava.com/#/walk/bayh-dole-act-university-patent-rights"}, {"id": "wikipedia-collaborative-open-knowledge", "name": "Wikipedia / collaborative open knowledge", "year": "2001 AD", "yearN": 2001, "zone": "network-age", "domain": "society", "constraint": "encyclopedia 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"https://ticks.iamkesava.com/#/walk/alphafold-3-all-biomolecule-structure-prediction"}, {"id": "nobel-prizes-for-ai-hinton-and-jumper", "name": "Nobel Prizes for AI / Hinton and Jumper", "year": "2024 AD", "yearN": 2024, "zone": "ai-era", "domain": "computing", "constraint": "AI/ML as an engineering discipline rather than fundamental science", "parents": 1, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/nobel-prizes-for-ai-hinton-and-jumper"}, {"id": "gemini-1-5-1m-token-context-window", "name": "Gemini 1.5 / 1M token context window", "year": "2024 AD", "yearN": 2024, "zone": "ai-era", "domain": "computing", "constraint": "AI context as limited to a few pages of text", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/gemini-1-5-1m-token-context-window"}, {"id": "ai-agents-autonomous-task-completion", "name": "AI agents / autonomous task completion", "year": "2024 AD", "yearN": 2024, "zone": "ai-era", "domain": "computing", "constraint": "AI as reactive 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"parents": 1, "children": 1, "url": "https://ticks.iamkesava.com/#/walk/gemini-2-0-flash-real-time-multimodal-ai"}, {"id": "ai-in-drug-discovery-first-ai-designed-drug-trials", "name": "AI in drug discovery / first AI-designed drug trials", "year": "2025 AD", "yearN": 2025, "zone": "ai-era", "domain": "medicine", "constraint": "drug candidate identification as requiring years of wet-lab experimentation", "parents": 3, "children": 0, "url": "https://ticks.iamkesava.com/#/walk/ai-in-drug-discovery-first-ai-designed-drug-trials"}, {"id": "deepseek-r1-china-reaches-frontier-ai", "name": "DeepSeek R1 / China reaches frontier AI", "year": "2025 AD", "yearN": 2025, "zone": "ai-era", "domain": "computing", "constraint": "frontier AI capability as exclusively a US-company achievement", "parents": 2, "children": 1, "url": "https://ticks.iamkesava.com/#/walk/deepseek-r1-china-reaches-frontier-ai"}, {"id": "claude-4-sustained-reasoning-and-multi-hour-tasks", "name": "Claude 4 / sustained reasoning 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"Pascaline / first mechanical calculator", "year": "1642 AD", "yearN": 1642, "zone": "early-modern", "domain": "computing", "constraint": "mechanizing arithmetic with automatic carry", "parents": 4, "children": 3, "url": "https://ticks.iamkesava.com/#/walk/pascaline-1642"}, {"id": "leibniz-step-reckoner", "name": "Leibniz step reckoner / four operations mechanized", "year": "1673 AD", "yearN": 1673, "zone": "early-modern", "domain": "computing", "constraint": "mechanical multiplication and division", "parents": 3, "children": 4, "url": "https://ticks.iamkesava.com/#/walk/leibniz-step-reckoner"}, {"id": "jacquard-loom", "name": "Jacquard loom / programmable punched cards", "year": "1804 AD", "yearN": 1804, "zone": "industrial", "domain": "computing", "constraint": "machines following stored, swappable instructions", "parents": 4, "children": 3, "url": "https://ticks.iamkesava.com/#/walk/jacquard-loom"}, {"id": "hipparchus-astrolabe", "name": "Astrolabe / analog astronomical computer", "year": "150 BC", "yearN": -150, "zone": "classical-empires", "domain": "computing", "constraint": "computing celestial positions and time without tables", "parents": 3, "children": 4, "url": "https://ticks.iamkesava.com/#/walk/hipparchus-astrolabe"}, {"id": "zuse-z3", "name": "Zuse Z3 / first programmable digital computer", "year": "1941 AD", "yearN": 1941, "zone": "electric-age", "domain": "computing", "constraint": "automatic, programmable digital computation", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/zuse-z3"}, {"id": "colossus-bletchley", "name": "Colossus / first programmable electronic computer", "year": "1944 AD", "yearN": 1944, "zone": "electric-age", "domain": "computing", "constraint": "electronic-speed cryptanalysis", "parents": 1, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/colossus-bletchley"}, {"id": "harvard-mark-i", "name": "Harvard Mark I / first automatic large-scale calculator", "year": "1944 AD", "yearN": 1944, "zone": "electric-age", "domain": "computing", "constraint": "long, automatic computational sequences", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/harvard-mark-i"}, {"id": "sketchpad-sutherland", "name": "Sketchpad (Sutherland) / interactive computer graphics", "year": "1963 AD", "yearN": 1963, "zone": "space-digital", "domain": "computing", "constraint": "drawing directly with a computer instead of typing instructions", "parents": 2, "children": 4, "url": "https://ticks.iamkesava.com/#/walk/sketchpad-sutherland"}, {"id": "eliza-weizenbaum", "name": "ELIZA (Weizenbaum) / first chatbot", "year": "1966 AD", "yearN": 1966, "zone": "space-digital", "domain": "computing", "constraint": "natural-language conversation with a machine", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/eliza-weizenbaum"}, {"id": "intel-1103-dram", "name": "Intel 1103 / DRAM kills magnetic core", "year": "1970 AD", "yearN": 1970, "zone": "space-digital", "domain": "computing", "constraint": "affordable solid-state main memory", "parents": 2, "children": 3, "url": "https://ticks.iamkesava.com/#/walk/intel-1103-dram"}, {"id": "plato-iv-touchscreen", "name": "PLATO IV touch panel / first touchscreen in classroom", "year": "1972 AD", "yearN": 1972, "zone": "space-digital", "domain": "computing", "constraint": "pointing at the screen instead of typing answers", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/plato-iv-touchscreen"}, {"id": "smalltalk-72", "name": "Smalltalk-72 (Kay) / object-oriented language", "year": "1972 AD", "yearN": 1972, "zone": "space-digital", "domain": "computing", "constraint": "programs as message-passing objects rather than procedures", "parents": 1, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/smalltalk-72"}, {"id": "sql-sequel-1974", "name": "SQL / SEQUEL relational query language", "year": "1974 AD", "yearN": 1974, "zone": "space-digital", "domain": "computing", "constraint": "querying data without writing pointer-walking code", "parents": 3, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/sql-sequel-1974"}, {"id": "rsa-encryption-1977", "name": "RSA encryption / practical public-key crypto", "year": "1977 AD", "yearN": 1977, "zone": "space-digital", "domain": "computing", "constraint": "sharing encrypted messages without exchanging keys in advance", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/rsa-encryption-1977"}, {"id": "smtp-rfc-821", "name": "SMTP / email protocol standardized", "year": "1982 AD", "yearN": 1982, "zone": "space-digital", "domain": "computing", "constraint": "interoperable email between heterogeneous systems", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/smtp-rfc-821"}, {"id": "backpropagation-1986", "name": "Backpropagation (Rumelhart, Hinton, Williams)", "year": "1986 AD", "yearN": 1986, "zone": "space-digital", "domain": "computing", "constraint": "training multi-layer 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"jeff-han-multitouch-2006", "name": "Jeff Han multi-touch demo (TED 2006)", "year": "2006 AD", "yearN": 2006, "zone": "network-age", "domain": "computing", "constraint": "multi-finger gestural interfaces at scale", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/jeff-han-multitouch-2006"}, {"id": "plato-meno-knowledge-as-recollection", "name": "Plato's Meno / knowledge as recollection", "year": "380 BC", "yearN": -380, "zone": "axial-age", "domain": "mind", "constraint": "Learning seen as input from outside, with no account of how new ideas could be recognized as true", "parents": 3, "children": 3, "url": "https://ticks.iamkesava.com/#/walk/plato-meno-knowledge-as-recollection"}, {"id": "buddha-five-aggregates-skandhas", "name": "Buddha / five aggregates analysis of mind", "year": "450 BC", "yearN": -450, "zone": "axial-age", "domain": "mind", "constraint": "The 'self' treated as a unitary substance, with no decomposition of subjective experience", "parents": 4, 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"url": "https://ticks.iamkesava.com/#/walk/grain-storage-and-granaries"}, {"id": "cattle-domestication", "name": "Cattle domestication", "year": "8500 BC", "yearN": -8500, "zone": "settled-world", "domain": "economics", "constraint": "subsistence economies without mobile wealth, draft power, or capital goods", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/cattle-domestication"}, {"id": "flax-cultivation-and-linen-production", "name": "Flax cultivation and linen production", "year": "7000 BC", "yearN": -7000, "zone": "settled-world", "domain": "economics", "constraint": "people lacked a durable, lightweight textile for trade and storage, relying on animal hides", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/flax-cultivation-and-linen-production"}, {"id": "clay-token-accounting", "name": "Clay token accounting in Mesopotamia", "year": "5000 BC", "yearN": -5000, "zone": "settled-world", "domain": "economics", "constraint": "tracking 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"constraint": "food could not be preserved or transported over long distances without spoiling", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/salt-preservation-civilization"}, {"id": "plow-invention-ard", "name": "Plow (ard) enables surplus agriculture", "year": "3500 BC", "yearN": -3500, "zone": "settled-world", "domain": "economics", "constraint": "agricultural output per worker was low, limiting surplus and specialization", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/plow-invention-ard"}, {"id": "bronze-smelting-tin-alloy", "name": "Bronze smelting (tin alloy)", "year": "3500 BC", "yearN": -3500, "zone": "settled-world", "domain": "economics", "constraint": "tools and weapons were limited to softer copper or stone", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/bronze-smelting-tin-alloy"}, {"id": "sumerian-temple-economy", "name": "Sumerian temple economy", "year": "3000 BC", "yearN": -3000, "zone": "first-civilizations", "domain": "economics", "constraint": "centralized redistribution of goods via religious authority was impossible before", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/sumerian-temple-economy"}, {"id": "standardized-weights-balance-scale", "name": "Balance scale with standardized weights", "year": "2600 BC", "yearN": -2600, "zone": "first-civilizations", "domain": "economics", "constraint": "fair, verifiable trade of bulk goods was impossible without consistent mass measurement", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/standardized-weights-balance-scale"}, {"id": "code-of-ur-nammu-price-controls", "name": "Code of Ur-Nammu price controls", "year": "2100 BC", "yearN": -2100, "zone": "first-civilizations", "domain": "economics", "constraint": "before, no written economic laws existed; after, fixed prices and penalties for fraud stabilized markets", "parents": 3, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/code-of-ur-nammu-price-controls"}, {"id": "babylonian-partnership-contracts", "name": "Babylonian partnership contracts", "year": "1754 BC", "yearN": -1754, "zone": "first-civilizations", "domain": "economics", "constraint": "pooled capital for trade expeditions was not formalized in written agreements", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/babylonian-partnership-contracts"}, {"id": "minoan-bronze-ingot-trade-oxhide-ingots", "name": "Oxhide ingot standardizes bulk copper trade", "year": "1600 BC", "yearN": -1600, "zone": "first-civilizations", "domain": "economics", "constraint": "Before, transporting raw metal in bulk was inefficient and unstandardized", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/minoan-bronze-ingot-trade-oxhide-ingots"}, {"id": "phoenician-alphabet-for-trade-records", "name": "Phoenician alphabet", "year": "1050 BC", "yearN": -1050, "zone": "first-civilizations", "domain": "economics", "constraint": "complex scripts limited literacy and record-keeping to specialists", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/phoenician-alphabet-for-trade-records"}, {"id": "shang-dynasty-bronze-spade-money", "name": "Bronze spade money", "year": "700 BC", "yearN": -700, "zone": "axial-age", "domain": "economics", "constraint": "before, barter and tool-money dominated Chinese trade; no standardized cast currency existed", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/shang-dynasty-bronze-spade-money"}, {"id": "chinese-iron-coinage", "name": "Spade money minted in Zhou dynasty China", "year": "640 BC", "yearN": -640, "zone": "axial-age", "domain": "economics", "constraint": "small-scale market transactions were limited by barter and lack of standardized coinage", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/chinese-iron-coinage"}, {"id": "indian-punch-marked-coins", "name": "Indian punch-marked coins", "year": "600 BC", "yearN": -600, "zone": "axial-age", "domain": "economics", "constraint": "standardized silver coinage for long-distance trade across the Indian subcontinent was impossible", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/indian-punch-marked-coins"}, {"id": "solon-seisachtheia-debt-reform", "name": "Solon's seisachtheia debt reform", "year": "594 BC", "yearN": -594, "zone": "axial-age", "domain": "economics", "constraint": "debt bondage and serfdom were widespread, with debtors enslaved or bound to creditors", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/solon-seisachtheia-debt-reform"}, {"id": "nabonidus-state-directed-trade", "name": "Nabonidus' state-directed trade", "year": "550 BC", "yearN": -550, "zone": "axial-age", "domain": "economics", "constraint": "royal monopoly on luxury goods via Arabian caravans", "parents": 2, "children": 3, "url": "https://ticks.iamkesava.com/#/walk/nabonidus-state-directed-trade"}, {"id": "persian-daric-gold-coin", "name": "Persian daric gold coin", "year": "521 BC", "yearN": -521, "zone": "axial-age", "domain": "economics", "constraint": "no standardized gold coin for uniform payments across the Achaemenid Empire", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/persian-daric-gold-coin"}, {"id": "chinese-state-granary-system", "name": "Chinese state granary system", "year": "500 BC", "yearN": -500, "zone": "axial-age", "domain": "economics", "constraint": "grain prices fluctuated wildly between bumper and poor harvests, causing scarcity or collapse", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/chinese-state-granary-system"}, {"id": "scythian-gold-trade-with-greeks", "name": "Scythian gold trade with Greeks", "year": "500 BC", "yearN": -500, "zone": "axial-age", "domain": "economics", "constraint": "steppe resources were isolated from Mediterranean economy", "parents": 2, "children": 3, "url": "https://ticks.iamkesava.com/#/walk/scythian-gold-trade-with-greeks"}, {"id": "athenian-silver-mining-boom", "name": "Athenian silver strike at Laurium", "year": "483 BC", "yearN": -483, "zone": "axial-age", "domain": "economics", "constraint": "Athens lacked funds to build a large navy", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/athenian-silver-mining-boom"}, {"id": "greek-public-auction-of-tax-farming", "name": "Greek public auction of tax farming", "year": "400 BC", "yearN": -400, "zone": "axial-age", "domain": "economics", "constraint": "tax collection was a fixed state function, not a market-traded right", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/greek-public-auction-of-tax-farming"}, {"id": "mauryan-land-revenue-system", "name": "Mauryan land revenue system", "year": "320 BC", "yearN": -320, "zone": "axial-age", "domain": "economics", "constraint": "tax rates were arbitrary before; after, a standardized 1/6th produce tax enabled predictable state income", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/mauryan-land-revenue-system"}, {"id": "appian-way", "name": "Appian Way", "year": "312 BC", "yearN": -312, "zone": "axial-age", "domain": "economics", "constraint": "overland transport was slow, costly, and limited to local routes", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/appian-way"}, {"id": "roman-silver-denarius", "name": "Roman silver denarius introduced", "year": "211 BC", "yearN": -211, "zone": "axial-age", "domain": "economics", "constraint": "before, Roman coinage was bronze; large transactions and military pay lacked a standard silver coin", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/roman-silver-denarius"}, {"id": "wu-zhu-coinage", "name": "Wu Zhu coinage standardizes Chinese bronze currency", "year": "118 BC", "yearN": -118, "zone": "classical-empires", "domain": "economics", "constraint": "Chinese coinage was unstable and debased, with no fixed weight standard", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/wu-zhu-coinage"}, {"id": "han-state-owned-workshops", "name": "Han state nationalizes salt and iron industries", "year": "117 BC", "yearN": -117, "zone": "classical-empires", "domain": "economics", "constraint": "private control of salt and iron production limited state revenue and military funding", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/han-state-owned-workshops"}, {"id": "roman-census-under-augustus", "name": "Roman census under Augustus", "year": "28 BC", "yearN": -28, "zone": "classical-empires", "domain": "economics", "constraint": "no empire-wide population data for taxation and conscription", "parents": 2, "children": 3, "url": "https://ticks.iamkesava.com/#/walk/roman-census-under-augustus"}, {"id": "mauryan-state-monopoly-on-mining", "name": "Arthashastra codifies state mining monopoly", "year": "100 AD", "yearN": 100, "zone": "classical-empires", "domain": "economics", "constraint": "private control of mineral extraction was impossible under Mauryan state monopoly", "parents": 3, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/mauryan-state-monopoly-on-mining"}, {"id": "barbegal-aqueduct-and-mills", "name": "Barbegal watermill complex", "year": "100 AD", "yearN": 100, "zone": "classical-empires", "domain": "economics", "constraint": "grain grinding was limited to human or animal power", "parents": 3, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/barbegal-aqueduct-and-mills"}, {"id": "roman-adoption-of-parchment-codex", "name": "Roman adoption of the parchment codex", "year": "100 AD", "yearN": 100, "zone": "classical-empires", "domain": "economics", "constraint": "scrolls were bulky, fragile, and limited in portability and ease of reference", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/roman-adoption-of-parchment-codex"}, {"id": "roman-tax-reform-under-diocletian", "name": "Diocletian's tax reform stabilizes late empire", "year": "297 AD", "yearN": 297, "zone": "classical-empires", "domain": "economics", "constraint": "tax collection was chaotic and uneven across the empire", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/roman-tax-reform-under-diocletian"}, {"id": "heavy-plough-in-northern-europe", "name": "Heavy plough in Northern Europe", "year": "600 AD", "yearN": 600, "zone": "post-classical", "domain": "agriculture", "constraint": "heavy clay soils were unworkable with earlier ploughs", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/heavy-plough-in-northern-europe"}, {"id": "tax-farming-in-islamic-caliphates", "name": "Tax farming in Islamic Caliphates", "year": "700 AD", "yearN": 700, "zone": "post-classical", "domain": "economics", "constraint": "state tax collection was inefficient and revenue streams were variable", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/tax-farming-in-islamic-caliphates"}, {"id": "mint-standardization-under-charlemagne", "name": "Charlemagne's silver penny reform", "year": "793 AD", "yearN": 793, "zone": "post-classical", "domain": "economics", "constraint": "coinage was chaotic and debased, limiting long-distance trade", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/mint-standardization-under-charlemagne"}, {"id": "horse-collar-in-europe", "name": "Horse collar adoption in Europe", "year": "1000 AD", "yearN": 1000, "zone": "post-classical", "domain": "economics", "constraint": "horses could not pull heavy loads without choking, limiting traction and power", "parents": 3, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/horse-collar-in-europe"}, {"id": "cog-ship-design-in-baltic", "name": "Cog ship design in Baltic", "year": "1000 AD", "yearN": 1000, "zone": "post-classical", "domain": "economics", "constraint": "before, ships had limited cargo capacity and could not operate efficiently in shallow waters", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/cog-ship-design-in-baltic"}, {"id": "guild-system-formalization", "name": "Guild system formalization", "year": "1100 AD", "yearN": 1100, "zone": "post-classical", "domain": "economics", "constraint": "before, craft quality and training were unregulated; after, guilds set standards, reduced fraud, and enabled reliable trade", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/guild-system-formalization"}, {"id": "bill-of-exchange-in-medieval-europe", "name": "Bill of exchange in medieval Europe", "year": "1200 AD", "yearN": 1200, "zone": "post-classical", "domain": "economics", "constraint": "cross-border trade required physical coin or barter", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/bill-of-exchange-in-medieval-europe"}, {"id": "silk-road-peak-under-mongol-empire", "name": "Silk Road under Mongol Empire", "year": "1250 AD", "yearN": 1250, "zone": "post-classical", "domain": "economics", "constraint": "overland trade was dangerous and slow due to banditry and political fragmentation", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/silk-road-peak-under-mongol-empire"}, {"id": "double-entry-bookkeeping-in-italian-city-states", "name": "Double-entry bookkeeping in Italian city-states", "year": "1299 AD", "yearN": 1299, "zone": "post-classical", "domain": "economics", "constraint": "merchants could not systematically track profits, errors, or fraud in financial records", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/double-entry-bookkeeping-in-italian-city-states"}, {"id": "insurance-in-genoa", "name": "First marine insurance contract in Genoa", "year": "1347 AD", "yearN": 1347, "zone": "post-classical", "domain": "economics", "constraint": "Ship loss was catastrophic and uninsurable for merchants", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/insurance-in-genoa"}, {"id": "florentine-catasto-tax", "name": "Florentine Catasto of 1427", "year": "1427 AD", "yearN": 1427, "zone": "early-modern", "domain": "economics", "constraint": "before, systematic property census for progressive taxation was impossible", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/florentine-catasto-tax"}, {"id": "antwerp-bourse-building", "name": "Antwerp Stock Exchange opens as first commodity exchange", "year": "1531 AD", "yearN": 1531, "zone": "early-modern", "domain": "economics", "constraint": "trading was limited to open streets or inadequate buildings without a centralized, regulated marketplace", "parents": 3, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/antwerp-bourse-building"}, {"id": "school-of-salamanca-just-price-theory", "name": "School of Salamanca develops subjective value theory", "year": "1540 AD", "yearN": 1540, "zone": "early-modern", "domain": "economics", "constraint": "Moral theology forbade interest and profit based on scarcity and risk", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/school-of-salamanca-just-price-theory"}, {"id": "usury-laws-relaxation", "name": "England legalized 10% interest on loans", "year": "1545 AD", "yearN": 1545, "zone": "early-modern", "domain": "economics", "constraint": "charging any interest on loans was illegal or considered sinful", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/usury-laws-relaxation"}, {"id": "dutch-east-india-company-annual-dividend", "name": "Dutch East India Company annual dividend", "year": "1602 AD", "yearN": 1602, "zone": "early-modern", "domain": "economics", "constraint": "profits were distributed irregularly, with no predictable investor returns", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/dutch-east-india-company-annual-dividend"}, {"id": "welser-family-bankruptcy", "name": "Welser family bankruptcy", "year": "1614 AD", "yearN": 1614, "zone": "early-modern", "domain": "economics", "constraint": "state defaults were rare; sovereign debt risk and limited liability necessity were not understood", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/welser-family-bankruptcy"}, {"id": "bank-of-hamburg", "name": "Bank of Hamburg issues Mark Banco", "year": "1619 AD", "yearN": 1619, "zone": "early-modern", "domain": "economics", "constraint": "trade was hampered by debased coinage and monetary instability", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/bank-of-hamburg"}, {"id": "sveriges-riksbank-charter", "name": "Sveriges Riksbank charter", "year": "1668 AD", "yearN": 1668, "zone": "early-modern", "domain": "economics", "constraint": "before, banks were private and could collapse from overissuing notes without state control", "parents": 3, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/sveriges-riksbank-charter"}, {"id": "guild-system-decline", "name": "Guild system decline", "year": "1700 AD", "yearN": 1700, "zone": "early-modern", "domain": "economics", "constraint": "production and trade were restricted by guild monopolies and regulations", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/guild-system-decline"}, {"id": "physiocracy-emergence", "name": "Physiocracy emerges as first economic theory", "year": "1756 AD", "yearN": 1756, "zone": "early-modern", "domain": "economics", "constraint": "wealth was seen as gold or trade surplus, not agricultural surplus", "parents": 2, "children": 3, "url": "https://ticks.iamkesava.com/#/walk/physiocracy-emergence"}, {"id": "samuel-slater-cotton-mill", "name": "Slater's first US textile mill", "year": "1790 AD", "yearN": 1790, "zone": "industrial", "domain": "economics", "constraint": "mechanized cotton spinning was impossible in the United States", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/samuel-slater-cotton-mill"}, {"id": "boulton-and-watt-steam-engine-patent-expires", "name": "Boulton & Watt steam engine patent expires", "year": "1800 AD", "yearN": 1800, "zone": "industrial", "domain": "economics", "constraint": "other inventors could not legally build efficient steam engines without paying royalties", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/boulton-and-watt-steam-engine-patent-expires"}, {"id": "north-river-steamboat", "name": "North River Steamboat demonstrates commercial steam navigation", "year": "1807 AD", "yearN": 1807, "zone": "industrial", "domain": "society", "constraint": "upstream river transport was slow and unreliable, limiting inland trade routes", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/north-river-steamboat"}, {"id": "luddite-machine-breaking-riots", "name": "Luddite machine-breaking riots", "year": "1811 AD", "yearN": 1811, "zone": "industrial", "domain": "economics", "constraint": "textile workers could not oppose automated machinery without risking execution or transportation", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/luddite-machine-breaking-riots"}, {"id": "cumberland-road-national-road-completed", "name": "Cumberland Road (National Road) completed", "year": "1818 AD", "yearN": 1818, "zone": "industrial", "domain": "economics", "constraint": "westward freight and settlement were slow and costly without a federally funded highway", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/cumberland-road-national-road-completed"}, {"id": "stockton-and-darlington-railway-opens", "name": "Stockton and Darlington Railway opens", "year": "1825 AD", "yearN": 1825, "zone": "industrial", "domain": "economics", "constraint": "overland freight was slow and expensive, limiting bulk commodity trade", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/stockton-and-darlington-railway-opens"}, {"id": "cooke-and-wheatstone-telegraph", "name": "Cooke and Wheatstone telegraph", "year": "1837 AD", "yearN": 1837, "zone": "industrial", "domain": "economics", "constraint": "long-distance communication was limited to the speed of physical transport", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/cooke-and-wheatstone-telegraph"}, {"id": "bank-charter-act-1844", "name": "Bank Charter Act 1844 (Peel's Act)", "year": "1844 AD", "yearN": 1844, "zone": "industrial", "domain": "economics", "constraint": "commercial banks could issue their own banknotes, and note issuance was not tied to gold reserves", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/bank-charter-act-1844"}, {"id": "california-gold-rush-begins", "name": "California Gold Rush", "year": "1848 AD", "yearN": 1848, "zone": "industrial", "domain": "economics", "constraint": "gold was scarce, limiting money supply and economic growth", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/california-gold-rush-begins"}, {"id": "refrigerated-railcar", "name": "Refrigerated boxcar enters service", "year": "1851 AD", "yearN": 1851, "zone": "industrial", "domain": "economics", "constraint": "perishable food could not be shipped long distances without spoilage", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/refrigerated-railcar"}, {"id": "limited-liability-act-1855", "name": "Limited Liability Act 1855", "year": "1855 AD", "yearN": 1855, "zone": "industrial", "domain": "economics", "constraint": "limited liability for corporations was not easily available to the general public", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/limited-liability-act-1855"}, {"id": "homestead-act", "name": "Homestead Act of 1862", "year": "1862 AD", "yearN": 1862, "zone": "industrial", "domain": "economics", "constraint": "land ownership was inaccessible to most settlers without capital", "parents": 2, "children": 3, "url": "https://ticks.iamkesava.com/#/walk/homestead-act"}, {"id": "national-bank-act", "name": "National Bank Act establishes uniform national currency", "year": "1863 AD", "yearN": 1863, "zone": "industrial", "domain": "economics", "constraint": "banknotes from different states circulated at steep discounts and wildcat banking was rampant", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/national-bank-act"}, {"id": "first-stock-ticker-gold-and-stock-telegraph", "name": "Stock ticker (Gold & Stock Telegraph)", "year": "1867 AD", "yearN": 1867, "zone": "industrial", "domain": "economics", "constraint": "stock prices could not be transmitted continuously over long distances in real time", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/first-stock-ticker-gold-and-stock-telegraph"}, {"id": "trade-union-act-1871", "name": "Trade Union Act 1871 legalizes unions", "year": "1871 AD", "yearN": 1871, "zone": "industrial", "domain": "economics", "constraint": "trade unions had no legal status and striking was suppressed", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/trade-union-act-1871"}, {"id": "typewriter", "name": "Typewriter", "year": "1874 AD", "yearN": 1874, "zone": "industrial", "domain": "economics", "constraint": "handwriting limited clerical speed and legibility in offices", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/typewriter"}, {"id": "telephone-exchange", "name": "Telephone exchange enables instant voice coordination", "year": "1878 AD", "yearN": 1878, "zone": "industrial", "domain": "economics", "constraint": "business communication was limited to telegraph or mail; telephone exchanges enabled instant voice coordination across cities", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/telephone-exchange"}, {"id": "compulsory-primary-education-laws", "name": "Compulsory primary education laws", "year": "1880 AD", "yearN": 1880, "zone": "industrial", "domain": "economics", "constraint": "illiteracy constrained industrial workforce; mandatory schooling created a trainable labor pool for complex manufacturing", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/compulsory-primary-education-laws"}, {"id": "pearl-street-station", "name": "Pearl Street Station powers first underground urban grid", "year": "1882 AD", "yearN": 1882, "zone": "industrial", "domain": "physics", "constraint": "factories and buildings had to be near water power or steam engines for mechanical drive", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/pearl-street-station"}, {"id": "pneumatic-tire-for-vehicles", "name": "Pneumatic tire for vehicles", "year": "1888 AD", "yearN": 1888, "zone": "industrial", "domain": "society", "constraint": "vehicles could not travel comfortably or quickly on rough roads due to rigid wheels", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/pneumatic-tire-for-vehicles"}, {"id": "mail-order-catalog-sears", "name": "Sears mail-order catalog expands beyond watches", "year": "1894 AD", "yearN": 1894, "zone": "industrial", "domain": "economics", "constraint": "rural consumers could not easily access a wide variety of urban goods without traveling to cities", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/mail-order-catalog-sears"}, {"id": "first-corporate-bond-rating-moodys", "name": "Moody's publishes first bond ratings", "year": "1909 AD", "yearN": 1909, "zone": "electric-age", "domain": "economics", "constraint": "standardized credit risk assessment for investors was impossible without published bond ratings", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/first-corporate-bond-rating-moodys"}, {"id": "first-electronic-funds-transfer-fedwire", "name": "Fedwire electronic funds transfer system", "year": "1918 AD", "yearN": 1918, "zone": "electric-age", "domain": "economics", "constraint": "interbank settlement required physical delivery of cash or gold", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/first-electronic-funds-transfer-fedwire"}, {"id": "mfs-investment-management", "name": "MFS launches first open-end mutual fund", "year": "1924 AD", "yearN": 1924, "zone": "electric-age", "domain": "economics", "constraint": "small investors could not access diversified pooled investments with daily liquidity", "parents": 3, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/mfs-investment-management"}, {"id": "bretton-woods-system-operational", "name": "Bretton Woods system becomes operational", "year": "1945 AD", "yearN": 1945, "zone": "electric-age", "domain": "economics", "constraint": "stable international monetary order was impossible without 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"container-shipping-standardized-iso", "name": "ISO standardizes intermodal container sizes", "year": "1968 AD", "yearN": 1968, "zone": "space-digital", "domain": "economics", "constraint": "efficient global freight logistics was impossible without standardized intermodal containers", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/container-shipping-standardized-iso"}, {"id": "nixon-shock", "name": "Nixon shock ends Bretton Woods system", "year": "1971 AD", "yearN": 1971, "zone": "space-digital", "domain": "economics", "constraint": "fixed exchange rates tied to gold limited national monetary policy", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/nixon-shock"}, {"id": "money-market-fund", "name": "Money market fund", "year": "1971 AD", "yearN": 1971, "zone": "space-digital", "domain": "economics", "constraint": "small savers could not earn market interest rates on short-term deposits due to Regulation Q caps", "parents": 2, "children": 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"dell-direct-to-consumer-model", "name": "Dell direct-to-consumer PC sales model", "year": "1984 AD", "yearN": 1984, "zone": "space-digital", "domain": "economics", "constraint": "computer sales required retail intermediaries and inventory", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/dell-direct-to-consumer-model"}, {"id": "world-wide-web-becomes-public", "name": "World Wide Web becomes public", "year": "1993 AD", "yearN": 1993, "zone": "space-digital", "domain": "computing", "constraint": "multimedia content was inaccessible to non-technical users", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/world-wide-web-becomes-public"}, {"id": "first-online-stock-trade-k-aufhauser", "name": "K. 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as accounting currency", "year": "1999 AD", "yearN": 1999, "zone": "network-age", "domain": "economics", "constraint": "cross-border european trade required currency exchange and hedging", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/euro-currency-launch"}, {"id": "alibaba-b2b-marketplace", "name": "Alibaba B2B marketplace", "year": "1999 AD", "yearN": 1999, "zone": "network-age", "domain": "economics", "constraint": "small Chinese manufacturers had no global wholesale channel", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/alibaba-b2b-marketplace"}, {"id": "y2k-bug-remediation-spending", "name": "Y2K bug remediation spending", "year": "1999 AD", "yearN": 1999, "zone": "network-age", "domain": "economics", "constraint": "legacy computer systems could not handle dates beyond 1999", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/y2k-bug-remediation-spending"}, {"id": "nasdaq-crossing-5000", "name": "NASDAQ 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"https://ticks.iamkesava.com/#/walk/ebay-acquisition-of-paypal"}, {"id": "sarbanes-oxley-act", "name": "Sarbanes–Oxley Act", "year": "2002 AD", "yearN": 2002, "zone": "network-age", "domain": "economics", "constraint": "corporate accounting fraud had no strong legal deterrent", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/sarbanes-oxley-act"}, {"id": "google-ipo", "name": "Google IPO", "year": "2004 AD", "yearN": 2004, "zone": "network-age", "domain": "economics", "constraint": "ad-supported search business model was unproven at scale", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/google-ipo"}, {"id": "m-pesa-mobile-money-launch", "name": "M-Pesa mobile money launch", "year": "2007 AD", "yearN": 2007, "zone": "network-age", "domain": "economics", "constraint": "unbanked populations had no access to digital payments", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/m-pesa-mobile-money-launch"}, {"id": "kickstarter-crowdfunding", "name": "Kickstarter launches crowdfunding platform", "year": "2009 AD", "yearN": 2009, "zone": "network-age", "domain": "economics", "constraint": "creative projects could not raise small amounts from many backers", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/kickstarter-crowdfunding"}, {"id": "libor-scandal-settlement", "name": "Libor scandal settlements expose rate-rigging", "year": "2012 AD", "yearN": 2012, "zone": "network-age", "domain": "economics", "constraint": "trust in interbank lending rates as honest benchmarks", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/libor-scandal-settlement"}, {"id": "flash-boys-and-hft-scrutiny", "name": "Flash Boys exposes HFT front-running", "year": "2014 AD", "yearN": 2014, "zone": "network-age", "domain": "economics", "constraint": "high-frequency trading's unfair advantage was invisible to retail investors", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/flash-boys-and-hft-scrutiny"}, {"id": "tether-stablecoin-dominance", "name": "Tether stablecoin launch", "year": "2014 AD", "yearN": 2014, "zone": "network-age", "domain": "economics", "constraint": "crypto exchanges lacked a dollar-pegged digital token for trading", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/tether-stablecoin-dominance"}, {"id": "brexit-referendum", "name": "UK votes to leave the European Union", "year": "2016 AD", "yearN": 2016, "zone": "network-age", "domain": "society", "constraint": "free movement of capital, goods, services, and people between the UK and EU", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/brexit-referendum"}, {"id": "nft-boom-cryptopunks", "name": "CryptoPunks launch NFT boom", "year": "2017 AD", "yearN": 2017, "zone": "network-age", "domain": "economics", "constraint": "digital art ownership could not be provably unique and tradable", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/nft-boom-cryptopunks"}, {"id": "gdpr-implementation", "name": "GDPR takes effect", "year": "2018 AD", "yearN": 2018, "zone": "network-age", "domain": "economics", "constraint": "unrestricted personal data monetization by tech firms", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/gdpr-implementation"}, {"id": "diem-digital-currency-announcement", "name": "Facebook announces Diem (Libra) stablecoin", "year": "2019 AD", "yearN": 2019, "zone": "network-age", "domain": "economics", "constraint": "a private corporation could not propose a global stablecoin payment system", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/diem-digital-currency-announcement"}, {"id": "gamestop-short-squeeze", "name": "GameStop short squeeze", "year": "2021 AD", "yearN": 2021, "zone": "ai-era", "domain": "economics", "constraint": "retail investors could not coordinate to squeeze hedge funds", "parents": 2, "children": 0, "url": "https://ticks.iamkesava.com/#/walk/gamestop-short-squeeze"}, {"id": "birch-bark-tar-adhesive", "name": "Birch bark tar adhesive", "year": "200,000 BC", "yearN": -200000, "zone": "deep-prehistory", "domain": "physics", "constraint": "hafting tools was unreliable without strong adhesive", "parents": 2, "children": 3, "url": "https://ticks.iamkesava.com/#/walk/birch-bark-tar-adhesive"}, {"id": "emergence-of-symbolic-behavior", "name": "Emergence of symbolic behavior", "year": "150,000 BC", "yearN": -150000, "zone": "deep-prehistory", "domain": "language", "constraint": "abstract representation of ideas was impossible", "parents": 2, "children": 3, "url": "https://ticks.iamkesava.com/#/walk/emergence-of-symbolic-behavior"}, {"id": "use-of-bone-for-symbolic-carving", "name": "Bone tools for symbolic carving", "year": "70,000 BC", "yearN": -70000, "zone": "cognitive-leap", "domain": "society", "constraint": "before, bone was rarely used for non-utilitarian objects", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/use-of-bone-for-symbolic-carving"}, {"id": "divje-babe-flute-2", "name": "Divje Babe flute (Neanderthal flute)", "year": "55,000 BC", "yearN": -55000, "zone": "cognitive-leap", "domain": "art", "constraint": "no known musical instruments or structured sound for social/ritual purposes before", "parents": 2, "children": 3, "url": "https://ticks.iamkesava.com/#/walk/divje-babe-flute-2"}, {"id": "microlith-technology", "name": "Microlith technology", "year": "40,000 BC", "yearN": -40000, "zone": "cognitive-leap", "domain": "computing", "constraint": "stone tools were large, single-piece, and difficult to repair or replace", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/microlith-technology"}, {"id": "figurative-sculpture-venus-figurines", "name": "Venus figurines (figurative sculpture)", "year": "35,000 BC", "yearN": -35000, "zone": "cognitive-leap", "domain": "art", "constraint": "no known 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"reid-founds-scottish-common-sense-philosophy", "name": "Reid publishes Inquiry on Common Sense", "year": "1764 AD", "yearN": 1764, "zone": "industrial", "domain": "mind", "constraint": "skepticism undermined knowledge of mind and perception", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/reid-founds-scottish-common-sense-philosophy"}, {"id": "galls-phrenology-system", "name": "Gall's phrenology system", "year": "1796 AD", "yearN": 1796, "zone": "industrial", "domain": "mind", "constraint": "no systematic mapping of mental faculties to brain regions", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/galls-phrenology-system"}, {"id": "cabanis-brain-secretes-thought", "name": "Cabanis: brain secretes thought", "year": "1802 AD", "yearN": 1802, "zone": "industrial", "domain": "mind", "constraint": "before, mind was considered immaterial; after, thought was a biological product", "parents": 2, "children": 2, "url": 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"mind", "constraint": "no standardized method to objectively measure children's cognitive ability for educational placement", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/stanford-binet-intelligence-scale"}, {"id": "watsons-psychology-as-the-behaviorist-views-it", "name": "Watson's methodological behaviorism", "year": "1924 AD", "yearN": 1924, "zone": "electric-age", "domain": "mind", "constraint": "psychology relied on introspection and untestable mental explanations", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/watsons-psychology-as-the-behaviorist-views-it"}, {"id": "skinner-box-development", "name": "Skinner box development", "year": "1938 AD", "yearN": 1938, "zone": "electric-age", "domain": "mind", "constraint": "precise study of operant conditioning and reinforcement schedules was impossible", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/skinner-box-development"}, {"id": "mcculloch-pitts-neuron-model", "name": "McCulloch-Pitts neuron model", "year": "1943 AD", "yearN": 1943, "zone": "electric-age", "domain": "mind", "constraint": "no formal mathematical model existed for neural computation", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/mcculloch-pitts-neuron-model"}, {"id": "transistor-invention", "name": "Transistor invented at Bell Labs", "year": "1947 AD", "yearN": 1947, "zone": "electric-age", "domain": "mind", "constraint": "vacuum tubes limited miniaturization, reliability, and power efficiency in electronics", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/transistor-invention"}, {"id": "wieners-cybernetics", "name": "Wiener's Cybernetics", "year": "1948 AD", "yearN": 1948, "zone": "electric-age", "domain": "mind", "constraint": "no unified theory existed for feedback control in machines and living systems", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/wieners-cybernetics"}, {"id": "turing-test-proposal", "name": "Turing test proposal", "year": "1950 AD", "yearN": 1950, "zone": "electric-age", "domain": "mind", "constraint": "no operational way to test whether machines can think", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/turing-test-proposal"}, {"id": "millers-magical-number-seven", "name": "Miller's magical number seven", "year": "1956 AD", "yearN": 1956, "zone": "electric-age", "domain": "mind", "constraint": "quantified limited capacity of human working memory", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/millers-magical-number-seven"}, {"id": "chomskys-universal-grammar", "name": "Chomsky's universal grammar theory", "year": "1957 AD", "yearN": 1957, "zone": "electric-age", "domain": "mind", "constraint": "behaviorist models could not explain how children acquire complex syntax from impoverished input", "parents": 3, "children": 3, "url": "https://ticks.iamkesava.com/#/walk/chomskys-universal-grammar"}, {"id": "chomskys-syntactic-structures", "name": "Chomsky's Syntactic Structures", "year": "1957 AD", "yearN": 1957, "zone": "electric-age", "domain": "mind", "constraint": "syntax was seen as dependent on meaning, and language as learned behavior", "parents": 3, "children": 3, "url": "https://ticks.iamkesava.com/#/walk/chomskys-syntactic-structures"}, {"id": "integrated-circuit", "name": "Integrated circuit dissolves discrete-component barrier", "year": "1958 AD", "yearN": 1958, "zone": "electric-age", "domain": "mind", "constraint": "discrete components prevented dense, cheap, and reliable electronic circuits", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/integrated-circuit"}, {"id": "hubel-and-wiesels-visual-cortex-work", "name": "Hubel and Wiesel discover orientation selectivity", "year": "1958 AD", "yearN": 1958, "zone": "electric-age", "domain": "mind", "constraint": "understanding of how the brain processes visual information was limited", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/hubel-and-wiesels-visual-cortex-work"}, {"id": "arpanet-first-message", "name": "ARPANET connects first computers", "year": "1969 AD", "yearN": 1969, "zone": "space-digital", "domain": "mind", "constraint": "no wide-area packet-switched network with distributed control existed for computer communication", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/arpanet-first-message"}, {"id": "working-memory-model-baddeley", "name": "Baddeley and Hitch's working memory model", "year": "1974 AD", "yearN": 1974, "zone": "space-digital", "domain": "mind", "constraint": "short-term memory was treated as a single, unified store", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/working-memory-model-baddeley"}, {"id": "flow-state-theory-csikszentmihalyi", "name": "Flow state theory (Csikszentmihalyi)", "year": "1975 AD", "yearN": 1975, "zone": "space-digital", "domain": "mind", "constraint": "optimal experience was undefined and unstudied as a measurable psychological state", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/flow-state-theory-csikszentmihalyi"}, {"id": "mindfulness-based-stress-reduction", "name": "Jon Kabat-Zinn founds MBSR program", "year": "1979 AD", "yearN": 1979, "zone": "space-digital", "domain": "mind", "constraint": "meditation lacked a standardized clinical protocol for empirical research", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/mindfulness-based-stress-reduction"}, {"id": "self-determination-theory", "name": "Self-determination theory (Deci/Ryan)", "year": "1985 AD", "yearN": 1985, "zone": "space-digital", "domain": "mind", "constraint": "human motivation was understood only through extrinsic rewards and punishments", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/self-determination-theory"}, 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{"id": "standing-army-in-france", "name": "Compagnie d'ordonnance established as first standing army", "year": "1445 AD", "yearN": 1445, "zone": "early-modern", "domain": "war", "constraint": "permanent professional force replaced ad hoc mercenary bands", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/standing-army-in-france"}, {"id": "treaty-of-tordesillas-2", "name": "Treaty of Tordesillas divides New World between Spain and Portugal", "year": "1494 AD", "yearN": 1494, "zone": "early-modern", "domain": "war", "constraint": "colonial claims in the New World were disputed without a clear boundary", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/treaty-of-tordesillas-2"}, {"id": "naval-line-of-battle-tactic", "name": "Line of battle tactic", "year": "1500 AD", "yearN": 1500, "zone": "early-modern", "domain": "war", "constraint": "ships could not fire broadsides without hitting friendly vessels", "parents": 2, "children": 2, "url": 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1949, "zone": "electric-age", "domain": "war", "constraint": "US nuclear monopoly constrained Cold War strategy and deterrence", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/soviet-nuclear-test"}, {"id": "soviet-spetsnaz-doctrine", "name": "Soviet Spetsnaz doctrine", "year": "1950 AD", "yearN": 1950, "zone": "electric-age", "domain": "war", "constraint": "deep-penetration sabotage and reconnaissance were ad hoc before dedicated special forces units", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/soviet-spetsnaz-doctrine"}, {"id": "suez-crisis", "name": "Suez Crisis ends UK and France as independent superpowers", "year": "1956 AD", "yearN": 1956, "zone": "electric-age", "domain": "war", "constraint": "colonial powers could act unilaterally without superpower consent", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/suez-crisis"}, {"id": "cuban-missile-crisis", "name": "Cuban Missile Crisis", "year": "1962 AD", "yearN": 1962, "zone": "space-digital", "domain": "war", "constraint": "direct superpower nuclear brinkmanship had not been tested", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/cuban-missile-crisis"}, {"id": "soviet-t-64-tank", "name": "Soviet T-64 tank", "year": "1963 AD", "yearN": 1963, "zone": "space-digital", "domain": "war", "constraint": "composite armor and autoloader were not combined in a main battle tank", "parents": 3, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/soviet-t-64-tank"}, {"id": "vietnam-war-body-count-metric", "name": "Vietnam War body count metric", "year": "1965 AD", "yearN": 1965, "zone": "space-digital", "domain": "war", "constraint": "measuring progress in counterinsurgency was subjective", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/vietnam-war-body-count-metric"}, {"id": "strategic-arms-limitation-talks", "name": "SALT I Treaty signed", "year": "1972 AD", "yearN": 1972, "zone": 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"us-army-adopts-m4-carbine", "name": "US Army adopts M4 carbine as standard", "year": "1994 AD", "yearN": 1994, "zone": "space-digital", "domain": "war", "constraint": "soldiers had to choose between heavy full-length rifles and underpowered submachine guns", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/us-army-adopts-m4-carbine"}, {"id": "bosnian-war-srebrenica-massacre-and-nato-intervention", "name": "Bosnian War ends with Dayton Accords", "year": "1995 AD", "yearN": 1995, "zone": "network-age", "domain": "war", "constraint": "peacekeeping was non-interventionist; air power for humanitarian intervention was taboo", "parents": 2, "children": 2, "url": "https://ticks.iamkesava.com/#/walk/bosnian-war-srebrenica-massacre-and-nato-intervention"}, {"id": "nato-bombing-of-yugoslavia", "name": "NATO bombing of Yugoslavia", "year": "1999 AD", "yearN": 1999, "zone": "network-age", "domain": "war", "constraint": "air power alone could not force a state's 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