PubMed1982
It is very interesting question whether time if a priori in mankind's thinking or whether it is a category which results from experience. Each human being has a memory so that he is able to distinguish between the past and the present, but not every language has a word expressing the common idea of time. In hunting and gathering populations such as Bushmen and Yumbri no one can state his own age. In chronobiology, the most important zeitgebers are the sun and the moon. Certain peasant peoples, such as the Santals and Mundas in India, even today use the same word to express sun, Sun-God, daylight, day, day-time, and hour. The first generalized idea of "time" seems to have arisen in the civilization of Old Mesopotamia. While the general meaning was still unknown to Sumerian, Accadian priest-astronomers presumably created the conception by generalization of the (Sumerian) foreign word itu(d) "mouth" and its mingling with the Accadian ittu(m) "sign (as an eclipse, monstrous birth, etc.), term, moment". We find the same root in the Etruscan itus "ides" from which it came as a loan-word into Latin (idus "ides"). Newton's term duratio can be found in earliest Iranian as yav- "yoke" and Vedic Indian as yugam "yoke" (i.e., a "bound" time). Some remarks are made concerning mankind's earliest chronobiological thinking where menstruation serves as a model. West African Kwa languages (predominantly Ewe), Old Indian, and early-classical chinese are evaluated. A brief survey is given of prehistoric peoples' migrations in terms of languages. The presentation concludes with an attempt to define time as an abstraction of abstractions, a fussy set (of ideas and definitions) in terms of post-classical set theory.