The Puranic time scheme is worked out in detail. Four yugas make a mahayuga of 4.32 million years. Seventy-one mahayugas make a manvantara, the reign of one Manu, and fourteen manvantaras with intervals make a kalpa of 4.32 billion years, which constitutes one day of Brahma. A night of equal length follows, during which the manifest worlds are withdrawn. Brahma lives a hundred such years, and then the whole structure resets.
The figures are internally consistent and were arrived at by a system that took its arithmetic seriously. That a day of Brahma lands within the same order of magnitude as the current estimate for the age of the earth is a coincidence worth noting without inflating, and the honest position is that these are cosmological schemes arrived at by different methods that happen to converge at one point. The tradition was not doing geology.
What the numbers are doing is more interesting than what they measure. A scheme this large makes the question how long ago was the beginning effectively unanswerable, because there is no beginning to locate: every kalpa is preceded by another, and Brahma himself is on a clock. Human history disappears entirely inside a single manvantara. The effect is deliberate deflation of the significance of any particular moment, including the present one, which is the same move made from the other direction by Hiranyagarbha, where each cycle begins from a golden womb rather than from nothing.
Kalpa and manvantara are units designed to be too large to identify with, which is precisely their function. To see how each cycle is said to begin, explore more of The Living Sanatan Timeline.
Part 77 of 100 — Series I: From the Beginning
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