Presuppositionalism is a Christian apologetic method that seems to be invading Christian theology as of late; ever since presuppositionalism was first promulgated by Cornelius Van Til it has been gaining more and more adherents. This, I believe, is to be expected, because presuppositionalism seems prima facie plausible and even intellectually appealing. Yet, after a closer glance towards the philosophical underpinnings of presuppositionalism, I maintain that it can be demonstrated to rest on egregious conflations and misunderstandings. It is one—there are many more—of these conflations that will occupy our attention at the present moment.
Let us begin with a quick formulation of presuppositionalism. Presuppositionalism is a method whereby one defends the Christian worldview, yet it attempts to complete this journey through a peculiar path. Presuppositionalism disagrees with all other methods of rational inquiry by beginning epistemologically with God, and scripture, whereas all other methods begin with man as their reference point. Presuppositionalism claims that every man adheres to an ultimate authority, and that the ultimate authority must be God and the Bible, as opposed to human autonomy. Moreover, since this authority is ultimate, it must be the light that illuminates all the facts we interpret. It must be the presupposition under which we bring our thoughts into conformity; that is, it must be the ultimate foundation that supports all our inferences. In his Defense of the Faith, Cornelius Van Til, the father of presuppositionalism, states the following:
It is the actual existence of the God of Christian theism and the infallible authority of Scripture which speaks to sinners of this God that must be taken as the presupposition of the intelligibility of any fact in the world.
A presupposition, as formulated in this context, is analogous to that of an axiom or a postulate. If something is presupposed then it is something which does not need justification, which is self-evident, and which provides the foundation for subsequent inferences—i.e. all premises can be traced back to this presupposition. Therefore, the presuppositionalist maintains that God and scripture must be one’s presupposition, and that this presupposition does not need justification, is self-evident, and provides the foundation for all rational inquiry. But, how does one arrive at such a thesis as claiming that God and scripture can be assumed as such a presupposition? Van Til articulates:
As Christians we hold that determinate human experience could work to no end, could work in accordance with no plan, and could not even get under way, if it were not for the existence of the absolute will of God. It is on this ground then that we hold to the absolute will of God as the presupposition of the will of man.
My interest is only to show that it takes an ultimate cause, God, if there are to be genuine second causes. In other words, it is only on the presupposition of the truth of Christianity that science is to be explained.
Van Til is claiming that if Christianity is true, then the whole of human experience depends ontologically on God. Therefore, our being depends on God’s being, and thus God’s consciousness must be presupposed in every instance of our consciousness.
Yet, this is where presuppositionalists have made a huge error. While the above formulations by Van Til seem appealing, to Christians, they, nevertheless, rest on a fallacious bait-and-switch whereby ontology is conflated with epistemology. That is, Van Til makes a claim regarding our existence being somehow dependent upon (or beginning with) God and then infers that our epistemology must also be dependent upon (and begin with) God. But, there is no reason to believe that the origin of being is equivalent to the origin of knowledge. Now, I as a Christian believe in God and, therefore, believe that our being is grounded in and finds its origination in God. But, this does not mean that our knowledge, therefore, must also begin with God. As R.C. Sproul says, “The order of being is not equivalent to the order of knowledge.” For example, our being is in some (secondary) sense caused by and begins with our parents, but it does not follow that our knowledge is also caused by and begins with our parents.
Furthermore, not only is the presuppositionalist’s jump from ontology to epistemology unwarranted, but, even if the jump were warranted, it seems to betray the nature of epistemology itself. For, in order for one to gain knowledge, they must begin with themselves—that is, with their own consciousness as their starting point (hence, Descartes cogito ergo sum). But, if we must begin with ourselves as the epistemological starting point, then how can we, as the presuppositionalist asserts, begin with God? Moreover, how is it even possible to begin outside of ourselves epistemologically? Surely such a venture is incoherent. Yet, this is what must take place if God and scripture are to be presupposed. Thus, it seems that presuppositionalists have simply misunderstood the nature of epistemology.
What we have witnessed is that the foundational claim of presuppositionalism—that God and scripture must be presupposed—rests on a conflation of ontology and epistemology, as well as a simple misunderstanding of the nature of how we acquire knowledge in the first place. A method that misconstrues so many fundamental aspects of philosophy should, obviously, not be adhered to.