Purva Mimamsa is unusual among schools this atlas classifies as religious philosophy for holding, consistently and on principle, that no creator god exists, a position the school did not arrive at reluctantly but built directly into its account of what makes the Veda authoritative in the first place. If the Veda had been composed by any author, human or divine, its authority would depend on that author's reliability, a fact that would then need establishing by some further evidence, and Mimamsa held that no such evidence exists and no such author is needed: the Veda is apaurusheya, without an author, eternal and self existent, so its injunctions carry authority simply as language correctly understood, with no composer standing behind them to vouch for what they say. A creator god who designed and produced the world was, on the same grounds, an unnecessary and unproven addition: the world's order could be explained, Mimamsa argued, by the eternal, self executing operation of ritual action and its unseen fruit, apurva, without invoking a divine agent to set it running or keep it running. Later Vedantins, building on the Upanishads Mimamsa left for the second half of the inquiry to address, generally did affirm a supreme reality, though not always a creator god in the familiar sense either, which makes Purva Mimamsa's flat denial one of the more striking positions in classical Indian religious thought: an elaborate, technically sophisticated system of ritual obligation, taken as binding and eternally authoritative, resting on no divine author, no divine creator and no divine judge anywhere in its architecture.