petitio principii

American  

[pi-tish-ee-oh prin-sip-ee-ahy, pe-tee-ti-oh pring-kip-i-ee] / pɪˈtɪʃ iˌoʊ prɪnˈsɪp iˌaɪ, pɛˈti tɪˌoʊ prɪŋˈkɪp ɪˌi /

noun

Logic.

1. a fallacy in reasoning resulting from the assumption of that which in the beginning was set forth to be proved; begging the question.

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petitio principii British  

/ pɪˈtɪʃɪˌəʊ prɪnˈkɪpɪˌaɪ /

noun

1. Sometimes shortened to: petitio.  logic a form of fallacious reasoning in which the conclusion has been assumed in the premises; begging the question

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Etymology

Origin of petitio principii

1525–35; < Medieval Latin petītiō prīncipiī, translation of Greek tò en archêi aiteîsthai the assumption at the outset

Example Sentences

See Examples For:

petitio principii

This mode of reasoning, by which a bad generalization is made to overrule all facts which contradict it, is petitio principii in one of its most palpable forms.

From A System of Logic: Ratiocinative and Inductive 7th Edition, Vol. II by Mill, John Stuart

Having thus quietly assumed that “things in themselves” are identical with “objects,” and “relations” with “impressions on the human mind,” Mr. Mill bases his whole criticism on this tacit petitio principii.

From The Philosophy of the Conditioned by Mansel, Henry Longueville

Such an argument is no argument at all; it is a mere petitio principii, incapable of proving anything.

From Supernatural Religion, Vol. I. (of III) An Inquiry into the Reality of Divine Revelation by Cassels, Walter Richard

The reviewer denies that there is a petitio principii in the syllogism, or that the proposition, All men are mortal, asserts or assumes that Socrates is mortal.

From A System Of Logic, Ratiocinative And Inductive (Vol. 1 of 2) by Mill, John Stuart

The Chaplain opportunely answered, "Your argument proves against yourself, for it is petitio principii to presuppose mortality amongst ephemera."

From The Campaner Thal and Other Writings by Jean Paul