Recently, I had some exchanges on Facebook regarding presuppositionalism:
1. Jonathan McLatchie
What is the trouble with the presuppositionalist school of apologetics? The presuppositionalist argues that Christianity is the only self-consistent worldview, and thus on that basis one is rationally warranted in taking it to be axiomatic -- thus, the presuppositionalist argues, it is impossible that Christianity is false because no other worldview is self-consistent. My beef with this view is at least two fold. First, coherence is not the only test of truth (indeed, there are many propositions which are self-consistent and yet false). There is also the correspondence test for truth -- in other words, does the proposition correspond to reality? Second, while I think a decent argument can be marshalled for asserting that theistic belief is axiomatic to the presumption of the rational intelligibility of the Universe, and indeed reason itself, it is not at all clear to me that the same is true of belief in the Bible as God's revealed Word. I fail to see any logical contradiction that is entailed by asserting that the Biblical worldview is false. That is why, in my opinion, evidentialism is far more satisfying as an apologetic approach.
Hays
Several distinctions are in order:
i) There's a difference between Clarkian presuppositionalism and Van Tilian presuppositionalism. Clark and Van Till represent opposing extremes. Clark is a rationalist while Van Til is a mystery-monger. I think Clark's rationalism is sometimes simplistic while Van Til is often gratuitously paradoxical.
Clark's epistemology is more Augustinian while Van Til's epistemology is more like a Reformed version of transcendental Thomism.
ii) The Clarkian version is axiomatic and espouses the coherence theory of truth.
One problem is that Gordon Clark had no real successors. There are some efforts to improve on his approach. To my knowledge, Ryan Hedrick is the most promising candidate to develop Clarkian presuppositionalism. But that remains at a programmatic stage.
ii) Van Til was a big picture thinker who didn't excel at detailed formulations. And he's binary to a fault.
Van Til's two leading, immediate successors were Greg Bahnsen and John Frame, both of whom diverge from Van Til in some respects.
iii) At present, the most astute Van Tililian apologist is probably James N. Anderson, although Vern Poythress also does some really find work in apologetics.
iv) The "logical contradiction that's entailed by asserting that the Biblical worldview is false" is the claim that God himself is the source and standard of logic and human rationality.
2. Suppose we take the crudest version of evidentialism, which would be akin to historical positivism. "Just the facts!"
Now when an evidentialist of that stripe tries to proves Christianity by appeal to the basic reliability of the Gospels, a halfway intelligent atheist will invoke Hume's argument for the presumption against miracles. Typically, an atheist will say that any naturalistic explanation, however implausible, is more plausible than a supernatural explanation.
That's why sophisticated evidentialists like Swinburne and the McGrews present a philosophical justification for the possibility and credibility of miracles. They do so to lay the groundwork for evidentialism.
By the same token, a key issue in the debate over ID theory is whether methodological atheism is a sine qua non of true scientific explanation. That's why Stephen Meyer and Bill Dembski, as well as sympathetic referees like Plantinga and Del Ratzsch, criticize methodological atheism.
Likewise, secularism is unable to justify induction and inductive logic. Or the first instance.
By contrast, as James Anderson pointed out some years ago, a doctrine of providentially preserved natural kind is able to ground induction.
On a related note are cliches about value-laden nature of observation, and the realist/antirealist debate over the philosophy of science.
These are examples of presuppositional issues in apologetics and related disciplines. So this is a crucial area in which evidential apologetics and Van Tilian apologetics overlap.
vi) That said, there's no doubt that much of the best work in contemporary Christian apologetic is hailing from the evidentialist camp.
3. Actually, the hardest things to prove can be obvious or fundamental things. That's because we use obvious or fundamental things to prove less obvious or less fundamental things. But once we hit bedrock, it's hard to directly prove what's intellectually bedrock. At that point the most promising line of argument is transcendental reasoning.
There are certain beliefs we don't normally attempt prove, such as the existence of other minds, an external world, or sense knowledge. And it's difficult, if not impossible, to prove them directly. Rather, we use these them to prove other things. And, in a roundabout way, that's the best way to prove these beliefs. We can't do without them. To deny them means to deny too many other things. Belief in God often operates at the same fundamental level.
Mind you, there can be more direct lines of evidence for God (e.g. miracles, answered prayer).
To take an example, W. V. Quine was the top secular philosopher of his generation. Labored to formulate a systematically naturalistic epistemology and ontology.
He started out as a mathematician. His initial reputation derived from his work on mathematical logic. However, as a consistent atheist, he denied logical necessity. That didn't fit into physicalism. He did admit to being a "reluctant platonist" to accommodate the higher ranges of set theory.
So, from a secular perspective, what is logic? Is logic just how human brains think (assuming brains do the thinking)? If so, what's the standard of comparison? What makes one brain logical and another brain illogical? If logic isn't independent of brains, then what's the basis for saying someone used a logical fallacy? Logic is nothing over and above how brains operate. Whose brain is the benchmark?
By contrast, Christian philosophers like Greg Welty and James Anderson have argued that abstract objects like logic are constituted by the infinite, timeless mind of God. That grounds logic in a way that naturalism/physicalism cannot.
4. Regarding Josh Parikh's infinite regress objection to Sye's brand of presuppositionalism, I think part of the problem may be Sye's equivocal, slipshod terminology about "making sense of X". Suppose we recast the issue using epistemic justification lingo. Suppose we then draw the following distinction. A belief can be justified in two different senses:
i) A person's state of belief may be justified or justifiable
ii) Providing a philosophical justification for a belief
If we're using "justified" in the sense of (ii), and if someone must presuppose Christian theism in that sense to be justified (="make sense of"), then that may well generate Josh's infinite regress. You can never get started if you must provide a preliminary philosophical justification for everything you say or believe. For every claim you make will then be unjustified absent a prior justification. In other words, if you're providing a justification for X, but the justification you provide requires a justification in its own right. I think that's the kind of regress that Josh is angling t.
One way to sidestep that deadlock is appeal to (i). We can begin in a state of justified belief. That psychological state may in turn be amenable to philosophical justification, so we can take it a step further. A justified belief in the sense of (i) can be subject to additional analysis and philosophical justification. To have a justified belief in the sense of (i) is the starting-point for having a justified belief in the sense of (ii).
So, for instance, a young child is justified in the sense of (i) in believing that he knows his mother by sight and his mother loves him.
And in principle, that might be justifiable in the sense of (ii) through corroborative evidence.
By analogy, unbelievers can hold many justified beliefs in the sense of (i) even if their atheism implicitly undermines those beliefs. Given atheism, they can't justify their beliefs in the sense of (ii), even though some of their beliefs are justified or justifiable in the sense of (i).
Josh may or may not agree with me, but it's an attempt to disambiguate the issue.
i) One issue is that you have different religious epistemologies which intersect with different apologetic methodologies. although the fit is sometimes adventitious.
For instance, there's the infallibilist tradition of the Westminster Confession, where a Christian can attain "infallible assurance" of the faith.
Towards the opposite end of the spectrum are apologists who consider dialogue with atheists to be genuinely open-ended. It could go either way.
These are deeper differences than apologetic method. And it often has a lot to do with the personal experience of individual apologists.
ii) A problem with Van Tilian apologetics is a shallow talent pool. Much shallower than the available pool for classical and evidential apologetics. A lot of what passes for Van Tilian apologetics doesn't get beyond the level of slogans.
On a related note is Sye ten Bruggencate, who has quite a following among people with low philosophical standards (to put it kindly).
iii) One further problem is a bad development within Van Tilian apologetics, where Oliphint, Nate Shannon, Dolezal, and even Poythress (who's head and shoulders above the other three) are on the warpath when it comes to univocity. That's a dead-end.
5. Sye Ten Bruggencate
They are indeed without excuse because the HAVE the evidence, so why are you giving them evidence when Scripture says they already have enough?
Hays
i) Enough for what? Enough to be culpable?
ii) Having enough evidence to know that God exists isn't the same thing as having enough evidence to know that Christianity is true. Assuming Rom 1 teaches that people generally have natural knowledge of God, it doesn't follow that people have natural knowledge of Christianity, for that is based on historical knowledge, and not something intuitive, innate, or inferable from reason or nature.
iii) There's a distinction between tacit knowledge and conscious knowledge. For instance, people of normal intelligence have a prereflective knowledge of informal logic and math (i.e. how to count).
But that tacit knowledge can be further developed through analysis.
iv) People can have enough evidence for something, but be in denial. As such, there are situations in which it's useful to present additional information to make their denial untenable.
Sye
I don't have any evidence that people have been saved by evidence.
Hays
It's unclear what that's even supposed to mean.
Sye
Give me one example where evidence was presented by Jesus and Paul for the existence of God. Just one please.
Hays
i) Of course, Jesus and Paul were typically dealing with Jewish theists or pagan polytheists.
ii) In addition, we need to guard against caricaturing sola Scriptura. Sola scripture doesn't mean the Bible is an encyclopedia. Many things are true that fall outside the purview of Scripture. The fact that you can't find something in Scripture doesn't ipso facto mean it's false or unwarranted.
Sye
Please show from Scripture that the 'atheist' does not believe in God. Thanks.
Hays
There's a potential distinction between knowing something and believing something. A wife may suspect that her husband is cheating on her. There's telltale evidence. But she refuses to believe it.
Sye
How about explain how you can make sense of ANYTHING without presupposing Christian Theism, thanks.
Hays
What does Sye mean by "making sense of x"? Seems to be a basic equivocation here. Surely it's possible to understand a sentence without presupposing Christian theism. You can "make sense of" what a sentence means without presupposing Christian theism.
So does Sye really mean something like you can't justify any of your beliefs without presupposing Christian theism?
Sye
How about you just tell us ONE thing you know without presupposing Christian theism and how YOU know it? Thanks.
Hays
What about a young child who knows the sound of his father's voice or recognizes his mother's face?
Sye
So you know something for certain, because it is not doubtable? is that your claim?
Josh used an example of a self-presenting state: pain. I can't be mistaken about feeling pain. I can be mistaken about the source of pain, but not pain itself.
BTW, this goes to the question of whether all knowledge is propositional.
6. Kelly K Klein
Wow, so that's it, it just seems to be the best explanation for you, I guess until someone convinces you to the contrary. You make your reason and acceptance the standards by which you determine God might exist?
Hays
i) Well, there's an obvious sense in which every Christian must rely on his own reason regarding what seems to be true to him. What's the alternative? You mind is the instrument by which you apprehend truth and falsehood. It's not as if you can climb out of your own skin and see things from a vantage-point independent of your own mind.
ii) There's an important distinction between knowledge and proof. It's possible to know things we can't prove. Indeed, that's commonplace. Take memory. We can know that something happened because we remember it happening, even though, in many cases, we may have no supporting evidence over and above our memories.
iii) There's a distinction between what I can know and what I can prove to someone else.
Klein
Why do you claim to be a Christian, is it because to you at the moment it just makes the most sense?
Hays
From a Reformed standpoint, it's ultimately up to God to conserve the faith of the elect.
Klein
But to others it doesn't make the most sense, so who is correct, according to you no one really knows.
Hays
There's a difference between mere belief and belief that's rationally defensible. Notice what a poor job the atheists on these comment threads do at defending their beliefs. Notice how often they resort to sheer assertions and diversionary tactics.
I listened to the Sproul/Bahnsen debate years ago. Sproul is a popularizer. Spreads himself very thin. He's hardly the most able exponent of classical apologetics. Bahnsen is more competent. But in that debate Bahnsen repeatedly committed the semantic fallacy of supposing you can infer a concept of knowledge from quoting a Greek word that's translated "knowledge".