Petitio Principii Definition

pə-tĭshē-ō prĭn-sĭpē-ē, -ē-ī
The fallacy of assuming in the premise of an argument the conclusion which is to be proved.
Webster's New World
  • petitio

Origin of Petitio Principii

  • From Latin petitio principii (literally “an assumption from the beginning"), calque of Ancient Greek τὸ ἐν ἀρχῇ αἰτεῖσθαι (to en archÄ“ aetÄ«sthae, “to assume from the beginning").

    From Wiktionary

  • Medieval Latin petītiō prīncipiī Latin petītiō request Latin prīncipiī genitive of prīncipium beginning

    From American Heritage Dictionary of the English Language, 5th Edition

Find Similar Words

Find similar words to petitio principii using the buttons below.

Words Starting With

Words Ending With


petitio principii

Word Length