There are several methods available to the Christian for answering questions about or, challenges to, Christianity from the unbeliever. One could engage in an inductive approach which is aligned more closely with the evidentialist method of doing apologetics. This approach claims to follow the evidence to conclude that God exists. Or, a person may take a more deductive approach, which is most closely aligned with the classical method of doing apologetics. This method employs logical arguments that conclude that God exists. The presuppositionalist usually prefers to employ what is termed, a transcendental argument (TA) in his or her approach for doing apologetics. This method is not quite inductive or deductive in its method even though it may appear to be deductive at times. This method seeks to demonstrate that God is the necessary condition for the intelligibility of human experience.
Disclaimer: The primary goal of this website is not advanced level apologetics. That fact should be kept in mind when reading articles like this one that introduce concepts whose tentacles extend into the more complicated workings of logic and philosophy. The goal is to focus on the basics. That said, the primary aim of this article is to provide you with minimal exposure to the basics of how the transcendental argument for God is employed in Christian apologetics.
Robert Stern has helped flesh out a definition in his book, Transcendental Arguments: The first, and perhaps most definitive feature, is that these arguments involve a claim of a distinctive form: namely, that one thing (X) is a necessary condition for the possibility of something else (Y), so that (it is said) the latter cannot obtain without the former.
The Basic Idea
Presuppositional apologetics takes a two-step approach when answering questions about Christian belief. First, the presuppositional approach is to step into the shoes of the non-Christian and ask how it is possible for the basic beliefs of the non-Christian to provide for the intelligibility of human experience. By human experience, I mean things like knowledge, morality, logic, language, existence, etc. These human experiences are those experiences that are taken to be uncontroversial in nature. So the Transcendental Argument for God takes basic human experience, any experience that is uncontroversial (all agree that humans experience X) and proceeds to argue that God is the necessary precondition for the intelligibility of that experience.
Logic as Necessary Proof for God
For example, what is the necessary condition, for logic. What has to be the case in order for logic to be the case. That humans experience logic is uncontroversial as far as it goes. Moreover, any attempt to argue against logic necessarily employs logic. You cannot argue against logic without affirming it. In fact, in a recent discussion with a group of atheists, I demonstrated that logic could not have been the creation of the human mind on the ground that the creation of logic presupposes the prior existence of logic. In other words, logical thinking would have been a condition for the creation or invention of logic. What this means is that logic had to exist prior to the human mind. But how is this possible? How could logic, an experience that requires a mind, exist prior to any mind? This is no small conundrum for the materialistic atheist. The answer for the Christian really isn’t that difficult. Nevertheless, this is where we, as Christians, must be do better. We must be better thinkers. Now, think about what a mind is and how a mind operates. At this point, it seems impossible to imagine a mind functioning at all without logic. I have tried to imagine a mind functioning apart from logic and I confess that I find such a scenario entirely impossible.
Logic is necessarily the case. Logic obtains in the current state of affairs. Now, imagine any possible world in which logic is not the case. Such a world is not possible. There is no possible world in which logic is not the case. What this means is that logic is necessarily the case. When I say that logic is necessarily the case, I mean that there isn’t any possible world in which logic doesn’t exist.
The human mind is not a necessary entity. Human beings are not necessary beings. There are logically possible worlds in which human beings do not exist. This is a serious problem for any atheist attempting to account for the existence of logic. The atheist must either deny that logic is necessary or he must deny the proposition that human beings are not necessary beings and admit that human beings are necessary beings. But if he denies that logic is necessary, he has to admit that logic is nothing more than a convention and if that is the case, logic really isn’t a law-like thing but can easily be set aside as we please when it is convenient. This leads to a radically subjective skepticism and irrationalism which is itself self-refuting. This path is closed to the atheist. Well, the atheist then only has one other option. If he cannot tinker with logic, perhaps he can tinker with the human being. Again, the atheist will have to adopt the position that the human being is a necessary being. But if he does so, this will mean that human existence is infinite, without beginning or end. But the atheist insists on evidence for such beliefs and the evidence is wholly lacking for the belief that humans are necessary beings. Second, if the atheist can posit an infinite, necessary human existence, why not God? It seems entirely permissible to accept God belief if one is going to accept the belief that humans are necessary beings.
This places the atheist in a position of denying the necessary properties of logic or affirming the necessary property of human existence. If the atheist does the former, he ends up in self-refutation because necessity of logic cannot be denied without affirming it. If the atheist does the latter, he has abandoned any objection he had to God belief. Either way the intelligibility of the experience of human logic serves as a powerful demonstration for God belief.
The second step is to ask the atheist to step into the shoes of the Christian. This, most atheists as simply unwilling to do. The Christian explains that the laws of logic are not creations. There was never a time and there is no possible world in which logic is not the case. This conviction is based on the Christian’s view of the nature of logic. Logic, for the Christian, is how God thinks. Logic comes from the mind of the God. It just is a property of God himself. And since God is a necessary being, existing infinitely and eternally in all possible worlds, so too does logic. This explains why logic seems irresistible. Humans are created in God’s image with a mind similar to God’s mind. Logic is felt to impose itself on the human mind. It transcends us. And the Christian understanding of God’s nature explains why this is the case. In other words, if it is the case that God exists, and that logic is a property of God, then we would expect logic to function in exactly the way it does. And so it is.
Now, TAG makes the bold claim that Christianity is proven true because of the impossibility of the contrary. And the contrary is impossible because it involves contradiction. In other words, every non-Christian worldview is proven to collapse under the weight of TAG. The idea is that only the Christian conception of God can account for the intelligibility of human experience. If God were different from the Christian conception of God, things like logic, morality, knowledge, language and so forth would prove to be unintelligible. Could there be another worldview available, as yet uninvented that could account for the intelligibility of human experience? Logically speaking, philosophically speaking, yes. Theologically speaking, on Christian presuppositions about the state of affairs as it has obtained? No.
The Form of the Argument
The Transcendental Argument for God generally takes the for form of Modus Ponens even though it is not a deductive argument. The properties of the conditional premise in TAG are different from those in a standard deductive argument.
Intelligibility –> God
This argument claims that God is the necessary condition for intelligibility. But it is not a deductive argument properly speaking because in a deductive argument, the denial of the condition entails the denial of the conclusion. This is not the case for transcendental arguments. In this case, the denial of the condition is impossible. One cannot deny intelligibility without engaging in a self-refuting claim. There is no intelligibility is a self-refuting proposition. It is like saying, “I cannot speak a word in English.” If it is true, then it is false. What this means is that the argument claims that God must be presupposed even to deny his existence. The argument would look like this:
Intelligibility –> God
In summary then, TAG is a very forceful and powerful way to answer questions and challenges issued against Christian belief. It is irrelevant that one could speculate that it fails to actually accomplishes the once-for-all death blow to all non-Christian worldviews that some TAG proponents claim. What is relevant is that in its execution with unbelievers, it is incredibly effective and efficient. And what matters more than anything else is that TAG takes Scripture as its final and supreme epistemic authority for all truth claims.