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

It may be represented, also, as a petitio principii, or reasoning in a circle,—since the proof that the will is determined by the strongest motive is no other than the fact that it is determined.

From A Review of Edwards's by Tappan, Henry Philip

Besides, the author, in this assertion, is guilty of a most glaring petitio principii.

From Know the Truth; A critique of the Hamiltonian Theory of Limitation by Jones, Jesse H.

Is it not, then, a petitio principii to say, that the fact ought to be disbelieved because the induction to it is complete?

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

Perhaps it might be said that in arguing, "All men are mortal, and you are a man," it is not so much ignoratio elenchi as petitio principii that you commit.

From Logic, Inductive and Deductive by Minto, William

It is incredible, but it is incontestably true: the only basis for the "Ideal" of the Anarchist-Communists, is this petitio principii, this "assumption" of the very thing that has to be proved.

From Anarchism and Socialism by Plekhanov, Georgii Valentinovich