RESEARCH BASE
Search 3,721 documents across 34 fields — every claim tier-rated by evidence
3,633 are the core, quality-scored corpus (34 lettered sections — see How We Work); the remaining 88 are cross-corpus synthesis documents (68 InterDocs, 12 Connections, 8 Theories) also indexed here.
899 results for "PER" — page 15 of 45
W_2_04 — Tibetan Buddhism, Bön, and Hidden Knowledge (Terma)
Tibet's religious traditions represent one of the world's most elaborate systems for the exploration and mapping of consciousness states — from the Six Yogas of Naropa to the Dzogchen practices of pristine awareness, fro
W_2_20 — Vedic Civilizations
The Vedic period (c. 1500–500 BCE) represents the formative era of Indian civilization, encompassing the composition of the Rig Veda (the oldest surviving Indo-European literary text), the development of the fire sacrifi
W_2_03 — Daoism and Chinese Alchemy
Daoism is one of the world's oldest continuous philosophical-religious traditions, originating in China by at least the 4th century BCE and likely much earlier. Its alchemical tradition encompasses both waidan (external
W_5_27 — Valdivia Culture: Oldest Pottery in the Americas
The Valdivia culture (~3500–1800 BCE) of coastal Ecuador produced the oldest known pottery in the Americas, making it one of the earliest complex societies in the Western Hemisphere. Discovered by Emilio Estrada in 1956
ZH_4_05 — Venus Across Cultures: Morning Star in Myth and Astronomy
Venus — the brightest object in the night sky after the Moon — has held a unique position in the astronomical traditions and mythologies of civilizations worldwide. Its distinctive synodic cycle of approximately 584 days
ZH_4_12 — Meteor Showers and Meteorite Veneration
Meteors (shooting stars) and meteorites (the stones that survive to reach Earth's surface) have been objects of wonder, fear, and veneration across human cultures for millennia. Major meteor showers — the Perseids, Leoni
ZH_4_06 — Comets and Meteors in Cultural History: Omens to Science
Throughout human history, comets — with their dramatic, unpredictable appearances and luminous tails stretching across the sky — have been among the most powerful celestial omens, inspiring fear, wonder, and interpretive
ZH_4_09 — Astronomical Petroglyphs and Rock Art
Humans have carved, painted, and pecked celestial imagery into rock surfaces for at least 10,000 years — and possibly far longer. Astronomical petroglyphs and pictographs are found on every inhabited continent: images of
ZH_3_01 — Maya Astronomical Science: Venus Tables, Eclipse Cycles
The ancient Maya (c. 2000 BCE–1500 CE, with the Classic period c. 250–900 CE) developed one of the most sophisticated astronomical traditions of the pre-modern world — rivaling and in some respects exceeding Babylonian m
ZH_3_13 — Women in Astronomy: Hypatia, Caroline Herschel, Henrietta Leavitt
Women have contributed to astronomy from antiquity to the present — often against formidable institutional barriers, many of which persisted well into the 20th century. Hypatia of Alexandria (~355–415 CE) was a renowned
ZH_5_17 — Ancient Variable Star Observations (Algol)
Algol (Beta Persei, the "Demon Star") — a second-magnitude eclipsing binary star in the constellation Perseus that dims dramatically every 2.867 days as its fainter companion transits the primary star — may have been rec
ZH_5_24 — Zoroastrian Astral Cosmology and Fire-Temple Astronomy
Zoroastrianism — one of the world's oldest continuously practiced religions, founded by Zarathustra (dates debated: c. 1500–600 BCE) in Greater Iran — embedded astronomical observation deeply into its cosmology, calendar
ZH_5_16 — Eclipse Prediction and the Saros Cycle
The Saros cycle — a period of approximately 6,585.3 days (18 years, 11 days, 8 hours) after which the Sun, Moon, and lunar nodes return to nearly identical relative positions — has been the primary tool for eclipse predi
ZH_2_05 — Japanese and Korean Astronomical Traditions
The astronomical traditions of Japan and Korea developed in close dialogue with Chinese astronomy — but were far from mere copies. Both civilizations adapted Chinese astronomical models, instruments, and calendrical meth
ZH_2_14 — Iatromathematics: Zodiac Man, Medical Astrology, and Celestial Healing
Iatromathematics (Greek: iatros = healer + mathēmatikos = astrologer/mathematician) was the systematic integration of astrology with medical diagnosis and treatment — a dominant medical paradigm in the Western world from
ZH_2_17 — Islamic Golden Age Astronomy: Observation, Innovation, and the Preservation of Knowledge
Islamic astronomy — the astronomical tradition developed in the Islamic world from the 8th through the 15th centuries CE — represents one of the most productive and consequential scientific enterprises in human history,
ZH_2_16 — Islamic Astronomical Tables (Zīj): Precision Observation and Computational Tradition from Baghdad to Samarkand
The zīj (Arabic: زيج, plural zījāt) is the Islamic astronomical handbook tradition — comprehensive sets of numerical tables and computational instructions enabling astronomers to calculate the positions of the Sun, Moon,
ZH_1_15 — Star Catalogs: From Hipparchus to Hipparcos and the Tycho Catalog
A star catalog — a systematic list of stars with their positions, magnitudes, and sometimes colors, proper motions, and spectral types — is the foundational document of observational astronomy. The compilation of ever mo
ZH_1_10 — Transit of Venus: Political Astronomy and Global Science
A transit of Venus — when the planet Venus crosses the disk of the Sun as seen from Earth — is among the rarest of predictable astronomical events, occurring in a pattern of pairs separated by ~8 years, with the pairs se
ZH_1_03 — Babylonian MUL.APIN and Mathematical Astronomy
Babylonian astronomy represents the first mathematical science in human history — the first tradition to develop quantitative, predictive models of celestial phenomena based on systematic observation and arithmetic calcu
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