In classical rhetoric and logic, begging the question is an informal fallacy that occurs when an argument's premises assume the truth of the conclusion, instead of supporting it. It is a type of circular reasoning: an argument that requires that the desired conclusion be true. This often occurs in an indirect way such that the fallacy's presence is hidden, or at least not easily apparent. In modern vernacular usage, however, begging the question is often used to mean 'raising the question' or 'suggesting the question'. Sometimes it is confused with 'dodging the question', an attempt to avoid it. The phrase begging the question originated in the 16th century as a mistranslation of the Latin petitio principii, which actually translates to 'assuming the initial point'. The original phrase used by Aristotle from which begging the question descends is: τὸ ἐξ ἀρχῆς (or sometimes ἐν ἀρχῇ) αἰτεῖν, 'asking for the initial thing.' Aristotle's intended meaning is closely tied to the type of dialectical argument he discusses in his Topics, book VIII: a formalized debate in which the defending party asserts a thesis that the attacking party must attempt to refute by asking yes-or-no questions and deducing some inconsistency between the responses and the original thesis. In this stylized form of debate, the proposition that the answerer undertakes to defend is called 'the initial thing' (τὸ ἐξ ἀρχῆς, τὸ ἐν ἀρχῇ) and one of the rules of the debate is that the questioner cannot simply ask for it (that would be trivial and uninteresting). Aristotle discusses this in Sophistical Refutations and in Prior Analytics book II, (64b, 34–65a 9, for circular reasoning see 57b, 18–59b, 1). The stylized dialectical exchanges Aristotle discusses in the Topics included rules for scoring the debate, and one important issue was precisely the matter of asking for the initial thing—which included not just making the actual thesis adopted by the answerer into a question, but also making a question out of a sentence that was too close to that thesis (for example, PA II 16). The term was translated into English from Latin in the 16th century. The Latin version, petitio principii, 'asking for the starting point', can be interpreted in different ways. Petitio (from peto), in the post-classical context in which the phrase arose, means assuming or postulating, but in the older classical sense means petition, request or beseeching. Principii, genitive of principium, means beginning, basis or premise (of an argument). Literally petitio principii means 'assuming the premise' or 'assuming the original point'. The Latin phrase comes from the Greek τὸ ἐν ἀρχῇ αἰτεῖσθαι (to en archei aiteisthai, 'asking the original point') in Aristotle's Prior Analytics II xvi 64b28–65a26: