The Taittiriya Upanishad offers one of the shortest formal definitions of Brahman in the entire corpus: satyam jnanam anantam brahma, usually rendered as truth, knowledge, infinity is Brahman. Three words, no verbs, no imagery. It reads like a definition should read, compact and precise. What it is actually doing, on inspection, is stranger than a definition: each of the three words works by excluding an alternative rather than asserting a positive content.
Satyam, truth, is set against what changes and passes away. In Vedic usage the word does not mean a correct statement; it means what actually holds, as opposed to what merely seems to. Calling Brahman satyam excludes anything provisional or temporary from counting as ultimate. Jnanam, knowledge, is not a fact Brahman happens to possess. The commentators are emphatic that Brahman does not know things the way a mind knows objects; Brahman simply is the fact of knowing, before it splits into a knower and a known. And anantam, infinity, denies limit in every direction at once, spatial, temporal, and qualitative, ruling out any boundary that would make Brahman one thing among others.
Put the three together and the definition has quietly defined nothing in the ordinary sense. It has instead closed off the three main ways something could fail to be ultimate: by being temporary, by being an object rather than the ground of knowing, or by being bounded. What remains after all three exclusions is not a fourth thing added to the list. It is what is left when nothing has been left out.
This is a strategy the Upanishads return to often, and the next piece in this series, on why the absolute is described only by removing things, follows the same method to its logical endpoint. Satyam jnanam anantam is an early and unusually compressed instance: a definition that works entirely by telling you what could not possibly be true of its subject, and trusting that the shape left behind is more accurate than anything a positive description could have managed.
Part 15 of 100 — Series I: From the Beginning
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