Van Til’s argument for Trinitarian Theism

We recently began looking at some presuppositional arguments from Van Til, as examined by James Anderson. One of Van Til’s more interesting arguments is one for the existence of a God that is not unitarian. Theoretically the same argument could be made for a God that exists in multiple persons of any number, not just 3. But for now, we will treat Christianity as the only worldview that has the requisite ontological commitments.

The argument is basically this: at the base level, reality is either fundamentally unity, diversity, or both. Reality being fundamentally unity or fundamentally diversity would undermine our knowledge of reality. Therefore if we are to know anything about reality, we must hold that reality is fundamentally both. Only Christianity presents a worldview under which this is true, so Christianity is true.

Here is Van Til:

As Christians, we hold that in this universe we deal with a derivative one and many, which can be brought into fruitful relation with one another because, back of both, we have in God the original One and Many. If we are to have coherence in our experience, there must be a correspondence of our experience to the eternally coherent experience of God. Human knowledge ultimately rests upon the internal coherence within the Godhead; our knowledge rests upon the ontological Trinity as its presupposition. (An Introduction to Systematic Theology, 23)

This is relatively easy to phrase in a more formal premise-conclusion form, so I won’t bother here. I am sure you can all reconstruct it.

What we must do now is justify the claim that under fundamental unity or under fundamental diversity, reality is not knowable.

 

Knowledge is impossible under diversity
Suppose that diversity is fundamental, and that every thing is distinct from every other thing. Knowledge therefore can only be had of individual things, and not categories. We can’t know things like “cats don’t like water” without all (or just most) cats having that property. But if there are no shared properties between objects, knowledge seems to be very difficult. We certainly want to affirm we have this kind of knowledge of classes and categories and groups, so we must deny that reality is fundamentally diverse.
Knowledge is impossible under unity
Under fundamental unity, where everything is at the base level the same kind of thing, knowledge seems impossible because there is nothing to differentiate one thing from another. We can only know that an object has a property A if there are some objects that do not have the property A. And perhaps more interestingly, if one knows something about an object, that it has a property A, it must be that we know it has a property A instead of property B. But under unity, there are no A and B, they are unified and identical. So between objects and within one object, knowledge depends on distinctions.
Isn’t it possible that fundamentally there are some things that are distinct and some that are similar?
Maybe. Suppose that this were the case, that fundamentally there are things of category A that are all the same and things of category B that are all the same (two kinds of monads) and they are entirely distinct from each other. We have distinction: Bs are not As. And we have unity. All As are As. This seems like it solves the problem of the unity/distinction tradeoff in the same way the Trinity does.
A possible monadology
Suppose that reality is fundamentally composed of monads, think of them like really small atoms for now. We cannot know one monad from another, other than by incidental properties like location or momentum (inasmuch as small objects have these). But these monads compose larger objects like chairs and cats. We can have knowledge about chairs and cats, they are real objects which share properties. They are unified and distinct in the right way. But they are composed of entirely unified monads. Where is the problem here? How would Van Til respond? I am not sure.
Conclusion
We are again seemingly left not totally convinced by Van Til. Maybe he is right that knowledge is impossible under fundamental unity and under fundamental diversity. But we don’t just know fundamentals, we know composites, and even if fundamentals are indistinguishable the composites aren’t.
More
Vern Poythress has done some interesting work expanding and explaining Van Til here, which I think is more promising than the work Van Til has done himself. But I am still not convinced that it is sufficient to demonstrate the existence of God.

Presuppositional Apologetics: One Helpful Approach Among Many

This is the title of a good post from the blog Reflections. Being Reformed, many people expect me to engage exclusively in presuppositional apologetics. Unfortunately for them, I am primarily interested in and gifted in more classical arguments such as cosmological arguments. And so I often get criticised on the basis of having an unbiblical anthropology, appealing to reason which the atheist has no ground or basis for.

I am however strongly convinced that scripture allows us to use other apologetic methodologies. Soon I intend to write a post explaining the biblical basis for using cosmological arguments. But until then, let this post from Reflections be the start of my explanation.

I respectfully think the standard presuppositionalist apologetics presentation is usually high on proclamation and rhetoric but sometimes low in terms of actual apologetic argument. Kelly James Clark notes this criticism in Five Views on Apologetics and I think there is merit to it. Thoughtful nonbelievers are not going to roll over and just admit that without God there is no possibility of having a coherent, morally viable, and existentially livable worldview. Don’t get me wrong: I think most of our worldview competitors do indeed have severe problems in explaining life’s most meaningful realities, but to say that all non-Christian worldviews are logically deficient needs to be demonstrated, not just proclaimed. In terms of philosophy, enduring aspects of Platonism, Aristotelianism, and Kantianism don’t strike me as absurd, and they do have unique elements that don’t appear to be merely borrowed from Christianity.

For example, is it possible that Jews and Muslims could presume the truth of their faith based upon their claimed revelation from God? And could Judaism and Islam attempt to justify a transcendental argument from their revelatory perspective? I know Cornelius Van Til appeals to the concept of the one and the many to support the unique unity and diversity with the Trinity. I appreciate his intuition, but again, I would like to see this kind of discussion furthered—especially when it comes to these two important revelatory-based world religions.

I have heard presuppositional apologists say that there is an appropriate time to use evidences for the Christian faith, such as support for the resurrection of Jesus. But in practice, I think this is seldom done. So could arguments from classical and evidential apologetics provide helpful elements to presuppositionalism? And, if so, when?