Is it possible to prove that God exists? That all depends on what is meant by the word prove.

If the question is whether it is possible to prove scientifically that God exists, then the answer is no. But that is not because belief in God is unreasonable or unsupported by evidence. It is because – by definition – God is not the sort of being whose existence is detectable by scientific investigation. The tools of science are well-suited to analyze those things that are part of the material world, things that can be put under a microscope or tested in a particle accelerator. Christianity (and Judaism and Islam) teaches that God is the creator of the universe, and as such, God exists outside of the material world. So in principle, God is not a fit subject for the empirical methods of science.

Since God’s existence cannot be proven scientifically, does that mean we are without any resources to establish his existence? This would be the case only if, as atheist author Dan Barker has asserted, “The scientific method is the only trustworthy means of obtaining knowledge” (Losing Faith in Faith, p. 133). Is science the only path to knowledge? There are two major problems with this assertion.

Here’s the first problem. If I asked Dan Barker how he came to know that “the scientific method is the only trustworthy means of obtaining knowledge,” what scientific evidence could he offer to support this contention? None. That’s because this assertion is not a scientific claim, but a philosophical claim. And since it is philosophical rather than scientific, the only way Barker could demonstrate that it is true is by using philosophical reasoning. But if he did this, then he would have to concede that the scientific method is not the only reliable means of obtaining knowledge, and that philosophical reasoning is also a valid path to truth. In other words, the only way Barker could defend his contention is by refuting it. So that’s the first problem with the view that the scientific method is the only reliable means of obtaining knowledge – it is a self-refuting claim.

But there is a second problem with this notion. The methods of science take for granted more fundamental truths about reality. Here are just a few of them:

  • There is a world outside of and independent of our minds. (Not everyone accepts this. Some people believe that, kind of like the movie The Matrix, there is no actual world beyond their mind, that what they think is a world filled with other people, places, and events is merely an illusion. We need to take special care of those people, because if they go, we all go with them!)
  • There are laws of mathematics and logic that we can use to study the natural world. (These cannot be proven by science – they are assumed by science in order to make scientific analysis possible.)
  • There is order in nature which we can rationally perceive. (This is why we think we can do science in the first place.)

All of these fundamental assumptions are necessary for the practice of science, yet none of them is established by the scientific method. So if it was really true that “the scientific method is the only reliable means of obtaining knowledge,” then the scientific enterprise could never get started, since it could never – on its own – establish the rationale for why science can get to work in the first place.

So if we are not limited by scientific proof, what other means is available to us to prove that God exists? The classical arguments for the existence of God combine simple observations of the natural world with basic logical deductions to arrive at the conclusion that God exists. The basic form of this reasoning is very similar to what we learned in high school geometry class. Do you remember how geometric proofs work? You begin with a “given,” and then you work step by step, employing the basic laws of logic and mathematics to derive a conclusion.

The arguments for God’s existence put forth through the centuries by great thinkers like Aristotle and Avicenna and Aquinas work just like this. They begin with a given, some simple and obvious observation about reality (like, “some things change,” or “some contingent things exist”). And then they methodically apply the laws of logic to these basic observations to deduce the existence of God.

Next week I want to begin a series of posts that will demonstrate such an argument for the existence of God.