As the saying goes, "People living in circular philosophies should not toss circular objections" -- or something like that.
A frequent charge against Presuppositional Apologetics is that it is a circular argument -- it presupposes Christian theism in order to prove Christian theism.
This objection comes from atheists -- who live in an irrational and circular philosophy -- but, amazingly, also comes from Christians.
This objection has been put forward by "Classical" Christian apologist Professor William Lane Craig. Craig writes in Five Views on Apologetics (p. 232-3):
To add to the perplexity, in Craig's criticism above, he pays a somewhat begrudging compliment to presuppositionalism, viz.
But there is a deeper hidden inconsistency in Craig's objections. When Craig says presuppositionalism is guilty of a "logical howler" we should ask, "To what logic is he appealing?" If he is presupposing logic as constituted in man by God, then he is presupposing Christian theism and is guilty of the same "logical howler." If he is not, then he is presupposing "neutral" logic -- in that case Craig is presupposing atheist logic, contrary to his Christian profession -- either way Craig's assertion is incoherent. Of course, we know this because presuppositionalism, contra Craig's "classical" apologetic, is consistently Christian. On the other hand, Craig's "classical" apologetic is blatantly anti-theistic. As Van Til repeatedly illustrated in his writings, Craig's apologetic adopts the unbeliever's standards of objectivity and the unbeliever's commitment to his autonomous reasoning as the ultimate authority. So then, Craig is not only arguing in a vicious circle, he is arguing from within the unbeliever's viciously circular presuppositions.
Bahnsen has addressed this false charge of circular argument repeatedly. Let me conclude with Greg Bahnsen's, succinct analysis from Pushing the Antithesis (p.123-5). Here is a corrected quote (omitted text is enclosed in brackets):
A frequent charge against Presuppositional Apologetics is that it is a circular argument -- it presupposes Christian theism in order to prove Christian theism.
This objection comes from atheists -- who live in an irrational and circular philosophy -- but, amazingly, also comes from Christians.
This objection has been put forward by "Classical" Christian apologist Professor William Lane Craig. Craig writes in Five Views on Apologetics (p. 232-3):
"As commonly understood, Presuppositionalism is guilty of a logical howler: it commits the informal fallacy of petitio principii, or begging the question, for it advocates presupposing the truth of Christian theism in order to prove Christian theism…A Christian theist himself will deny that question-begging arguments prove anything…But at the heart of presuppositionalism lies an argument, often not clearly understood or articulated, which is very powerful. This is an epistemological transcendental argument…"C.L. Bolt, on Choosing Hats has posted an analysis of William Lane Craig's objections to presuppositionalism (quoted above) in his post, William Lane Craig's Inconsistent Objections to Presuppositional Argument. In summary, C.L. Bolt points out the glaring inconsistency of Craig's objection: Craig claims on one hand that TAG has never been "spelled out" adequately but then asserts that TAG is circular ("guilty of a logical howler").
To add to the perplexity, in Craig's criticism above, he pays a somewhat begrudging compliment to presuppositionalism, viz.
"But at the heart of presuppositionalism lies an argument, often not clearly understood or articulated, which is very powerful. This is an epistemological transcendental argument…"So then, apparently TAG has been spelled out sufficiently for Craig to recognize the power of TAG. If TAG is powerful, then one wonders how it is committing a "logical howler!" Craig cannot have his cake and eat it too, as another famous saying goes.
But there is a deeper hidden inconsistency in Craig's objections. When Craig says presuppositionalism is guilty of a "logical howler" we should ask, "To what logic is he appealing?" If he is presupposing logic as constituted in man by God, then he is presupposing Christian theism and is guilty of the same "logical howler." If he is not, then he is presupposing "neutral" logic -- in that case Craig is presupposing atheist logic, contrary to his Christian profession -- either way Craig's assertion is incoherent. Of course, we know this because presuppositionalism, contra Craig's "classical" apologetic, is consistently Christian. On the other hand, Craig's "classical" apologetic is blatantly anti-theistic. As Van Til repeatedly illustrated in his writings, Craig's apologetic adopts the unbeliever's standards of objectivity and the unbeliever's commitment to his autonomous reasoning as the ultimate authority. So then, Craig is not only arguing in a vicious circle, he is arguing from within the unbeliever's viciously circular presuppositions.
Bahnsen has addressed this false charge of circular argument repeatedly. Let me conclude with Greg Bahnsen's, succinct analysis from Pushing the Antithesis (p.123-5). Here is a corrected quote (omitted text is enclosed in brackets):
"Before moving to our next response against the anti-metaphysical bias, you should be aware of a possible response that the unbeliever will bring against you. He will complain that you are engaging in circular reasoning or the informal logical fallacy of begging the question. That is, since we assert that God is self-verifying, we are assuming God in order to prove God. However, we should note in response to this objection:
(1) We are not engaged in special pleading for the Christian worldview. We are simply asking which system makes human experience intelligible. For sake of argument, we will grant the unbeliever his system with whatever foundations he adopts in order to see if it can justify its truth claims. But then he will have to grant us ours (for sake of argument) to see if we can justify our truth claims. By the very nature of our God as the self-existing, eternal Creator, our worldview self-justifies its starting point. (We will later explain this two-step procedure of worldview critique.)
(2) All systems must ultimately involve some circularity in reasoning. For instance, when you argue for the legitimacy of the laws of logic, you must employ the laws of logic. How else can you justify laws of logic? This is a transcendental issue, an issue that lies outside of the temporal, changing realm of sense experience. Laws of logic do not change: they are universal, invariant, abstract principles.
(3) "Circularity" in one's philosophical system is just another name for 'consistency' in outlook throughout one's system. That is, one's starting point and final conclusion cohere with each other. Here it is more fully explained:
The "circularity" of a transcendental argument is not at all the same as the fallacious 'circularity' of an argument in which the conclusion is a restatement (in one form or another) of one of its premises. Rather, it is the circularity involved in a coherent theory (where all the parts are consistent with or assume each other) and which is required when one reasons about a precondition for reasoning. [Because autonomous philosophy does not provide the preconditions for rationality or reasoning,] its "circles" are destructive of human thought--i.e. "vicious" and futile endeavors.(4) The unbeliever has no defensible standard whereby he can judge the Christian position. His argument either ends up in infinite regress (making it impossible to prove), has no justification (rendering it subjective), or engages in an unjustifiable same-plane circularity (causing it to be fallacious). Without a self-verifying standard, he has no epistemological way out. And only the Christian worldview has such a self-verifying standard.