In
logic, begging the question describes a type of
logical fallacy, petitio principii, in which the conclusion of an argument is implicitly or explicitly assumed in one of the premises. Stephen Barker explains the fallacy in The Elements of Logic: "If the premises are related to the conclusion in such an intimate way that the speaker and listeners could not have less reason to doubt the premise than they have to doubt the conclusion, then the argument is worthless as a proof, even though the link between premises and conclusion may have the most cast-iron rigor". In other words, the argument fails to prove anything because it takes for granted what it is supposed to prove.
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