Author Jason Lisle promises an "irrefutable argument for biblical creation and the Christian worldview in general." (128) Unfortunately, his supposed "ultimate proof" fails its own standards of proof and thereby disproves itself.
Lisle's ultimate proof consists of the following syllogism:
PREMISE 1: Only if biblical creation is true can we have genuine knowledge of things.
PREMISE 2: We have genuine knowledge of things.
CONCLUSION: Biblical creation is true.
While the technical form of this argument is valid its soundness depends on the truth of the premises, and therein lies the rub. Lisle proposes a three-pronged test for validating one's premises and presuppositions. They must be (1) logically consistent, (2) non-arbitrary, and (3) able to account for the preconditions of intelligibility. Lisle's ultimate proof is skewered by all three prongs.
I. THE ULTIMATE PROOF IS NOT SHOWN TO BE LOGICALLY CONSISTENT
Lisle states that the presuppositions of a worldview must be logically consistent. Even one seemingly insignificant contradiction will invalidate an entire worldview because from that single contradiction it is "literally possible to reach any conclusion whatsoever" no matter how absurd. (121) Lisle repeatedly asserts that the Bible is internally consistent and that it provides the only logically consistent worldview.
Lisle advises Christians to challenge every non-Christian worldview on the basis of internal inconsistency. But when the consistency of the Bible is challenged, Lisle advises Christians to plead the Fifth: "don't answer," he says. (63) Rather than demonstrating the Bible's internal consistency, Lisle recommends avoiding the issue with this dodge: "I don't accept your claim that the Bible is full of contradictions. ... But for the sake of argument, if it did, why in your worldview would that be wrong?" (63) Here we have a blatant example of the fallacy of special pleading.
As Lisle describes it, special pleading is "the fallacy of applying a double standard" in that "the arguer has applied a standard to his opponent that he does not apply to himself." (101) That is exactly what Lisle has done with the standard of logical consistency. He applies it to all other worldviews, but not to his own. While baldly asserting that the Bible is internally consistent, he never demonstrates that to be true and does not even allow the standard to be applied to the Bible. His "ultimate proof" therefore fails its own standard of logical consistency.
II. THE ULTIMATE PROOF IS ARBITRARY
The second test of the validity of one's presuppositions is that they must not be arbitrary, by which Lisle means that there must be a good, independent reason for them. (8, 45) His ultimate proof fails this test as well.
On obvious aspect of ultimate proof is its circularity. The proof, says Lisle, is that the Bible "must be true because if it were not, we could not actually know anything at all." (26) Both the truth of the Bible and its ability to account for knowledge are presupposed in the premises of this argument. Lisle readily admits this circularity and says that it is unavoidable. (129) He says there are two types of circular reasoning, one valid and one not, and claims that the ultimate proof utilizes valid circular reasoning.
Invalid "vicious circles" are those that "merely assume what they try to prove." (110) On the other hand, a good circular argument does not merely assume its conclusion but "goes out of its plane" and "imports additional information to support its conclusion." (129) Lisle claims the ultimate proof is not a vicious circle because it imports additional information. He writes, "The Christian circle is not a vicious circle but one that can account for all human experience and reasoning." (130) Again he says that the ultimate proof is not a vicious circle because it argues, "The Bible must be the Word of God because it says so and if you reject this claim you are reduced to foolishness." (130) But there is no "additional information" here; the argument does not "go out of its plane." The two quoted statements from page 130 are merely restatements of Premise 1 that "only if biblical creation is true can we have genuine knowledge of things." The ultimate proof merely assumes what it tries to prove and is therefore an invalid vicious circle.
Lisle fails to provide a good, independent reason for the ultimate proof that is not already assumed by its premises. That makes the argument arbitrary by Lisle's own definition and it therefore fails the second prong of Lisle's test.
III. THE ULTIMATE PROOF DOES NOT ACCOUNT FOR THE PRECONDITIONS OF INTELLIGILITY
The third prong requires that a worldview account for the preconditions of intelligibility. These preconditions include, among other things, the laws of logic, the uniformity of nature, the reliability of the senses, and the reliability of memory. To account for these preconditions, one must be able to answer the question "Why does it exist in the first place?" (38) The ultimate proof does not provide such an accounting.
Lisle asserts that "the preconditions of intelligibility are all found in the biblical God." (Loc. 3152) But Lisle never accounts for the biblical God by answering the question, "Why does God exist in the first place?" He has therefore failed to account for the preconditions of intelligibility under the third prong of his test.
Lisle is precluded from claiming that because God is the ultimate standard by and for which all other things are accounted He need not be accounted for Himself. Lisle insists that "if a person's ultimate standard cannot be proved, then that person does not actually know anything!" (128) Lisle has not accounted for his ultimate standard, and you know what that means.
The Ultimate Proof of Creation has proven too much, and too little. It has proven itself to be unsound, while failing to prove that its author does actually know anything.