Begging the question has traditionally been thought to be a fallacy because it is a breaking of the rules of the old-fashioned game of
elenchus (two-person contestive question-reply argumentation as found in Aristotle). Each participant has a conclusion (question) to be proved, and one of the rules was that a question must not directly ask for conclusion. This rule makes sense
within the framework of the game of elenchus, but argumentation on a serious matter is trying to get at the truth, to
know something.
Aristotle's question-answer games were irrelevant, as serious models of knowledge-seeking, and the prohibition of begging the question is not a law of logic, but only the rule of an old-fashioned competitive game. As some have said, "
To appeal to it when engaged in the scientific search for truth is as irrelevant as to obey the Queensbury rules when attacked by a murderer". In short, the fallacy of begging the question has no relevance to any pragmatic knowledge-seeking inquiry into the truth of a matter, as a proper criticism or alleged fallacy of argument.
The fallacy of begging the question always presupposes a context of disputation, and we can take this to imply that question-begging by one party in the disputation only occurs where his argument is directed to another party in the disputation who disbelieves the conclusion. The central purpose of argument is to show that something is worthy of belief. But this purpose can be accomplished even if the conclusion was initially neither believed nor disbelieved, or if the conclusion has been believed all along.
There are two levels of reasonable dialogue. At the abstract level, a game of dialogue is a normative model - a precisely stated set of rules forming an abstract structure that may or may not correspond in greater or lesser degrees to realistic contexts of argumentation.
At the practical level, a game of dialogue is a sequence of speech events - a regulated sequence of questions and answers that represents interactive persuasive argument exchanges between two parties on a controversial or disputed issue.
Real life is seldom either as simple or as reasonable as the ideal of the critical discussion, where the roles and rules of discussion are defined by rules that order and regulate permissible moves and replies.
In persuasion dialogue, the increment of knowledge is not only in coming to learn the strengths and weaknesses of an argument, but the deepening of the understanding of both one's own position and that of one's opponent.
It is a curious paradox of persuasion dialogue that real knowledge of one's position in argument comes only through the process of learning that one did not really know as decisively as one thought in the beginning that one's convictions are true. In persuasion dialogue, the strength to defend a position is achieved through learning the worst weaknesses in it.
For more, see:
http://www.researchgate.net/publication/226155441_Begging_the_question_as_a_pragmatic_fallacy
Per Van Til, a circular argument of a kind is unavoidable when we argue for an ultimate standard of truth. One who believes that human reason is the ultimate standard can argue that view only by appealing to reason. One who believes that the Bible is the ultimate standard can argue only by appealing to the Bible. Since all positions partake equally of circularity at this level, it cannot be a point of criticism against any of them.
See:
http://www.frame-poythress.org/presuppositional-apologetics/
http://thirdmill.org/files/english/html/pt/PT.h.Frame.Presupp.Apol.1.html
http://thirdmill.org/files/english/html/pt/PT.h.Frame.Presupp.Apol.2.html