Typically those of a more Arminian (or Arminian leaning) theology, who emphasize the idea of human freedom and responsibility, more often prefer Classical and/or Evidential apologetics. The reason for this is they believe the primary issue in conversion is that a person needs to believe the gospel is true (which is correct), and the way people exercise faith/belief comes about by receiving enough evidence to be convinced (which is false, in my opinion). In other words, for Arminians, the problem of unbelief is largely a problem of ignorance of the facts and a failure on the Christian's part to persuade the unbeliever that Christianity is true and that they need to believe it.
On the other hand those of a Reformed/Calvinistic theology, who emphasize the idea of God's sovereignty over all things, including the individual election of all who will be saved, more often prefer Presuppositional apologetics. Reformed thinkers recognize (along with their Arminian brothers and sisters) that faith/belief is central in the conversion of the lost, but they disagree with the perspective which identifies ignorance or lack of persuasion as the reason people do not believe; rather, they understand the reason people do not believe is because they are dead in their sin and need God to regenerate their heart and give them faith and repentance to believe. As such the reformed apologist presupposes the truth of Christianity and the Bible and argues that one cannot make sense of the world we live in unless Christianity is acknowledged as the truth, and people cannot be saved apart from the work of regeneration that God alone does.
So the issue is not the method of apologetics; the issue is the beliefs (presuppositions) of the apologist in relationship to theology and the means by which God saves people. So the two views are: (1) God saves by the gospel being preached and defended persuasively through philosophy and evidence (Arminian) and (2) God saves by the Gospel being preached and God giving the hearer a new heart with which to believe (Calvinism/Reformed). Another way to say it is that Arminians believe that arguments and evidence can be the decisive factor which brings people to faith, whereas Calvinists do not. Stated conversely, Calvinists believe that God's act of regeneration is the decisive factor which brings people to faith, whereas Arminians do not.
So the issue, at its base, is theological and not methodological. Theological conviction comes first and typically predisposes people towards a certain approach to apologetics. However typically Calvinist/Reformed thinkers are drawn towards strict presuppositionalism, and typically Arminian thinkers are drawn toward Classical and/or Evidential apologetics. This is merely a description of how things often are but is not prescriptive of how they must be. In fact, one example will demonstrate how much overlap there already is between the methods.
The Moral Argument for God's existence is a Classical argument because it fits within the two step methodology of proving the existence of God (Theism) before proving Christian theism in particular. Although this argument is not, strictly speaking, an evidential argument, most evidentialists I know think well of this argument. Interestingly, this argument is, at its core, presuppositional in nature. Here is the argument stated in deductive form:
(1) If objective moral values exist, then God exists.
(2) Objective moral values exist.
(C) Therefore God exists.
Let us unpack this a bit. The argument is relatively simple, despite the fact that it is misunderstood and/or misrepresented by atheists on a regular basis. The argument is simply stating that if there are objective moral values, such as "murder is wrong" and "telling the truth is good", then there must be sufficient grounds for such claims to be objective, that is, true regardless and apart from whether people believe it or know it to be true. An objective moral value is something which transcends individuals, culture and time. If it is objectively true, then it is true for everyone, everywhere and in every time. Such a thing cannot possibly be grounded in individual opinion, for individuals disagree about morals all the time. Such a thing cannot be cultural because cultures come into conflict on moral issues (e.g. Nazi Germany versus the Allied Forces). So if objective moral values exist, they must find their ground in something beyond individuals, beyond societies, beyond humanity itself. A moral law giver, such as God, is the only sufficient explanation. So if objective moral values exist, then it is necessarily the case that God exists.
Now it is not my purpose here to defend premise one but only to establish what is being said. Nor am I going to argue in this post for premise two that "Objective moral values exist". My point here is only to establish the nature of the argument being made. If objective moral values exist, then God exists. But while this is a classical apologetics argument, it is clearly presuppositional also. It says you cannot make sense of the fact that there are objective moral values unless you presuppose God exists. If you presuppose God's existence, then you have an adequate foundation for explaining the moral realities you see, experience and participate in every day. If you deny God's existence then you live inconsistently with your own worldview.
The classical argument is 'objective moral values, therefore God' and the presuppositional argument is 'God, therefore objective moral values.' But this is a distinction without a difference. It is actually the very same argument that is being made. So the Moral Argument serves us well to show that, methodologically speaking, Classical apologetics and Presuppositionalism are not mutually exclusive.
Furthermore, if you listen to good apologists of various stripes, you will see that often Classical and Evidential apologists are questioning the validity of their opponents' presuppositions and that Presuppositionalists often cite evidence and use philosophical reasoning to make their case. The fact is the void which exists between apologetics methodologies is very thin. The real chasm is not between methodologies; it is between theologies. I would encourage apologists to drink deeply from the well of all three methods of apologetics and learn to blend their approaches to be more effective. Understand that theology precedes method and that what you may not like about Presuppositionalism or what you may not like about Evidentialism or Classcialism is not their method, it is their theology. You can disagree with their theological presuppositions and still learn from their methodology.
The apostle Paul utilizes all three methods of apologetics throughout the book of Acts, and therefore, we should too. As a theologically reformed Christian, I suggest that only presupposing God's existence and the truth of what is communicated in Scripture can we make sense of the world around us. Even so, I am willing to defend Christian truth by utilizing philosophical argumentation and historical evidence. God, in his divine sovereignty and election, works through means. Romans 10 follows Romans 9. God elects unto salvation, but the word must be preached, heard and accepted. God may uses evidential and classical apologetics in the process of preparing people to receive new hearts in regeneration.
In reality, if Presuppositional apologetics works for Christianity, it is because Christianity is actually true. And if Christianity is actually true, then we can expect it to cohere with good philosophy and the historical evidence that is available. This is why neither Presuppositionalism nor Classical apologetics nor Evidential apologetics ultimately work for false religions like Islam or Mormonism or Buddhism, etc. Christianity is true and, therefore, can be demonstrated as such from numerous different approaches.
One last thought. Apologetics is not merely about evangelism (although it ought to be a large part of our evangelistic efforts). Apologetics strengthens the faith and confidence of believers, and this is where I think Presuppositionalists should be able to agree wholeheartedly that philosophy and evidence come alongside and reinforce what the word of God already tells us is true. If God exists, as we presuppose, and if His word is true, as we presuppose, then we should expect that what we find in philosophy and evidence would cohere with that.
