petitio principii


pe·​ti·​tio prin·​ci·​pii pə-ˈtē-tē-ˌō-(ˌ)priŋ-ˈki-pē-ˌē How to pronounce petitio principii (audio)
: a logical fallacy in which a premise is assumed to be true without warrant or in which what is to be proved is implicitly taken for granted

Examples of petitio principii in a Sentence

Recent Examples on the Web In the Middle Ages, Aristotle’s phrasing was translated into Latin as petitio principii. Melissa Mohr, The Christian Science Monitor, 16 May 2022

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'petitio principii.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History


Medieval Latin, literally, postulation of the beginning, begging the question

First Known Use

circa 1531, in the meaning defined above

Time Traveler
The first known use of petitio principii was circa 1531

Dictionary Entries Near petitio principii

Cite this Entry

“Petitio principii.” Dictionary, Merriam-Webster, Accessed 24 Sep. 2023.

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