ASK CHALCEDON ~ Presuppositional Certainty

I have a question concerning presuppositonal apologetics. I hope you can help.

If a religion was discovered tomorrow with its sacred writings and this religion agreed with all the essential doctrines of Christianity except for one essential doctrine, and the religion had strong external and internal proofs that validated it, how would a Christian presuppositionalist be certain that his/her presuppositonalism is correct, and thus deem the discovered religion a false religion? How would a presuppositionalist "know" this?

Thank you in advance for the answers. N. G.

Presuppositionalism is not contentless. A presupposition is a precontemplative commitment that deals with factuality in an epistemologically coherent way. You cannot, for example, reply to the challenge “define the taste of strawberry” without you and the other party to the dialogue having prior experience of the taste of a strawberry. 

This hypothetical “Religion H” would not exist in a neutral background, whereby an observer can evaluate the claims of Christianity and Religion H’s “sacred book” against a common set of criteria. The Bible itself makes this enterprise impossible when it states “To the law and to the testimony: if they speak not according to these, it is because there is no light in them” (Isa. 8:20) and “the spirit of the prophets is subject to the prophets” (1 Cor. 14:32). If even an angel from heaven preach a gospel in conflict with what was revealed, he is accursed (Gal. 1:8). There is irreconcilable conflict between the Bible and every other claimant to truth. Christianity is defended as a system, not piecemeal, so that it stands or falls together. 

In Cornelius Van Til’s “Introduction to Systematic Theology,” pgs. 164-65, he writes, “…in his mental grasp or understanding of anything, man is at each point dependent upon a prior act of unchangeable understanding and revelation on the part of God. The form of the revelation of God to man must come to man in accordance with his creaturely limitations. God’s thought with respect to anything is a unit. Yet it pertains to a multiplicity of objects. But man can think of that unit as involving a number of items only in the form of succession. So Scripture speaks of God as though He were thinking His thoughts step by step. All revelation is anthropomorphic. When God reveals Himself to man He reveals something of the fullness of His being. In God’s mind any bit of information that He gives to man is set in the fullness of His one supreme act of self-affirmation.” 

From the moral side of the equation, we’re in more serious straits. The attempt to weigh the Bible against The Book of H would require us sitting as judge and jury on God’s claims and the claims of the deity of The Book of H. This requires us to presuppose the competing claims to be on the same level, while we rise above that level as arbiter of truth. This process subordinates God’s claims under our own claim to rule over and adjudicate His claims. It is the essence of autonomy, of the rebellion of man against his Creator, to assert this right to deny God’s claim and assert man’s claim over God: to dethrone God and crawl onto His throne ourselves. To entertain the question is to have already dethroned God, because His ultimate claim has already been treated as contingent or false. And so man places his foot on God’s throat in such an epistemological setting. 

Under presuppositionalism, to entertain the question of “internal proofs” and “external proofs” that offer some alleged “validation” outside of the boundaries of the Christian worldview is AGAIN to pre-emptively dethrone God in the thinking process. These “proofs” are actually attempts (as Van Til put it) to “raise the specter of brute factuality” (because the discovery of H, and these alleged proofs, are being put forward as brute facts supposedly “requiring” autonomous interpretation at man’s hand). In presuppositionalism, as Van Til notes, you do not argue over fact but probe rather the underlying philosophy of fact. Further, possibility itself is governed by God, not God governed by abstract possibility. We have with God what is known as cosmic personal determinism, and that provides a robust intellectual platform that alone maintains coherence. 

Let’s drill down further: when you speak of internal proofs, this refers to internal coherence, and when you speak of external proofs, this refers to external correspondence. Neither coherence nor correspondence establish truth under presuppositionalism: only conformity to God’s revealed word delivers truth, because only those claims are anchored ontologically in His Being and character as He has revealed Himself to us. So important is His revealed word that we read, “Thou hast magnified Thy Word above all Thy Name” (Psalm 138:2). So the integrity of His revelation is set forward as ultimate. It’s not much of an ultimate authority if you don’t treat it as such, if you instead put man’s autonomous reason first to adjudicate the conflicting claims between the Bible and the Book of H. 

And even IF you undertook to catalog such a set of autonomously-derived, so-called “validations,” they are worthless. A valid argument, logically speaking, is one that is structurally true, such that if the premises are true, the conclusion is also true. What you need are not valid arguments but sound arguments (a sound argument is a valid argument where the premises are known to be true). But the law of contradiction (which is derived from the character of God, and is NOT antecedent to Him or over Him in any way, but subordinate and derivative and a reflection of His nature) asserts that A and Not-A cannot both be true in the same sense at the same time.  So the Christian worldview necessarily sits in judgment on Religion H and its claims: it undercuts the foundational premises of Religion H and the Book of H so that the best that could be claimed for it is logical validity, but not soundness (which in practical terms means it is false). Thus, this “validation” is a formal property only, not a fundamental property, and ultimately is the result of a process of abstraction and negation (Van Til is a valuable guide in understanding these issues).

Note, also, that when you use the term "strong" in respect to "proof," you should technically be speaking only of inductive proofs, and this opens up another can of worms entirely: whether or not the inductive process gives you anything better than probabilities, while raising the specter of uncertainty that plagues all inductive proof. Much has been written on induction by presuppositional apologists (as well as how to avoid the twin issues of a priori and a posteriori reasoning). The upshot is that under biblical presuppositionalism, you arrive at the very certainty that induction renders inaccessible. So it isn't possible to topple a presuppositionally coherent worldview that delivers epistemological certainty using an inductive argument that can only put forward probabilities. Besides, under biblical presuppositionalism, possibility is itself governed by God and delimited by Him: it is not an independent realm of contingency over God. 

The presuppositionalist knows because he/she is not autonomous in his/her reasoning. For he/she to be brought to a skepticism concerning the Bible, he/she must first abandon presuppositionalism and God’s epistemic authority while dethroning God and re-enacting Adam and Eve’s sin. It was, after all, a conflict of truth claims that took place in Eden – the hypothetical scenario you’re proposing is identical in essence but not detail (the detail isn’t important, what’s important to the challenge is simply to contradict what God said and entice the protagonist to move from being a creature UNDER God to the position of an autonomous judge OVER God – induce the creature to adjudicate and thus put God on the same level as the other claimant to truth).