On God, Proof, and Knowledge

by Matthew L. Halsted

When it comes to debating the “existence of God,” one of the preliminary questions that needs to be addressed is, What does proof look like in a debate like this? In other words, How can one display evidence or “prove” that God does (or does not) exist? Below are a few of my musings on this question.

I think we need to define what we mean by “proof.” When that word is used, there is often the implied idea that it entails a type of certainty. For instance, most people tend to think that in order to “prove” something is the case, one needs to have hard, indisputable evidence for it—maybe like empirical evidence, something a person could see or touch, maybe even video evidence or something like that. We might call this “scientific evidence”–evidence that can be tested, verified, falsified. Of course, empirical evidence like this would indeed constitute “proof” in certain situations. If, for example, I am inquiring into whether or not a man named Jones committed a crime, and there was DNA evidence found at the scene of the crime that can be linked back to Jones, then I would have some “proof”—some would say I could even be fairly certain—that he is in fact guilty of the crime in question. The problem, however, is that I don’t think the question of God’s existence needs to be narrowed down to the mere category of “scientific proof” like this. We need a broader category to work with. That is, I think we need to talk about knowledge in general.

When we say a person “knows” this or that thing, is hard evidence always entailed? Is this sort of proof always a necessary requirement? I don’t think so. Here’s why: There are many things that people claim to know (and can claim with confidence, I might add) without ever having “scientific proof” or even certainty. For example, suppose a guy named Sam was born on March 1, 1980, and suppose further that he knows this is his birthday. But how does he “know” he was born on that date? Can Sam be absolutely certain about knowing this? Well, no. After all, what if his parents were lying to him? What if his parents were part of a grand scheme to deceive him, making him think he is, in fact, two years older than he really is? At any rate, how could Sam ever discover with certainty—using scientific evidence—that he was truly born on March 1, 1980? Perhaps, he could find the doctor who delivered him, and maybe the doctor could confirm the date of his birth. But how is this “scientific proof” in the sense of certainty? Could it not be possible that the doctor, too, was part of the conspiracy? Does showing him the birth certificate help? Hardly. It could have been forged, after all. How can Sam, then, ground his knowing the date of his birthday? How can he ever claim to “know” when his birthday is? Better yet, how can you know when your birthday is? The truth is that everyone bases many of their fundamental knowledge claims not merely upon scientific-empirical evidence or even certainty, but rather upon reliability. So, you can claim to “know” that your birthday is the date it is because you presume from the outset the reliability of your parents’ testimony and of the birth certificate as an historical document. Of course, this is far from “certainty” in the proper sense of the word. (As said above, it could be the case that your parents are lying for some nefarious reason. You cannot simply appeal to a birth certificate as “empirical proof” since that document could have been fabricated.) But even though you cannot prove when you were born, this does not mean it is irrational to say you “know” when you were born. Proof, in this sense, isn’t a requirement for knowledge.

The point is that it’s quite okay to make some truth claims (e.g., “I was born on March 1, 1980”) without having to appeal to certainty or to scientific methodology as a necessary criterion. The knowing of your birth date simply resides beyond the scope of scientific considerations. Your parents’ presumed reliable testimony, your assumption that most birth certificates are accurate, your participating in the yearly celebrations, etc., are all sufficient for your knowing your birthday. More can be said here, but space does not permit.

Furthermore, people hold to other more substantial beliefs that are also not provable (in the above sense). For example, a 30-year old person can’t prove that the past three decades were not implanted into his/her consciousness a mere five minutes ago, with built in memories, feelings, etc., to create the false belief that he or she really existed the whole timeCan you “prove” that your life—or all of reality—is not the product of a mad scientist’s experiment? This is a silly question, but the point is actually fairly significant: How can you empirically and scientifically prove that this is not, in fact, the case?

But it just seems absurd to believe that all of reality is the product of a mad scientist’s experiment. Most rational people believe it isn’t, right? And too, rational people do not have to give reasons for why they are not an experiment of a malevolent scientist; it is perfectly rational to reject such beliefs—and without proof and argument. To say that a person requires “hard” proof that he or she is, in fact, not a “brain in a vat” seems absurd. We don’t have to prove our beliefs that the world, or that people in the world, are real. In fact, these beliefs are something we always assume rather than prove. These are what philosophers call “properly basic beliefs.” They are called “basic” because they are beliefs which are not argued for, but upon which all other beliefs rest. I don’t need to prove that the sum of 2 and 1 is 3. Rather, 2 and 1 being 3 is a basic belief upon which I am able to build all my other beliefs (e.g., more complex mathematical beliefs).

When I participated in a debate on the existence of God, one of the questions that got brought up was, “Can a person know that God exists?” My sparring partners (the atheists) seemed to have assumed that all knowledge must come through the scientific method. That is, in order to “know” anything at all, one must be able to test and verify it. I’ve noticed many atheists make this mistake. For them, in order to “know some thing,” the belief about the thing itself needs to be repeatable and empirically confirmed. And since God, and claims about him, cannot be physically touched, seen, or tested, belief in God cannot be anything other than just that–mere belief. One cannot say, then, that they “know” God truly exists. It seems that, for many atheists at least, unless one can scientifically test or repeat a truth claim (or belief), then one simply cannot say that the said belief is “true” or “false.” But this is clearly absurd, for we rationally and justifiably claim to know things all the time without testing them or repeating them (e.g., historical claims like our birthdays; see above). The truth, too, is that some beliefs are properly basic. The truth is that some truths can be known immediately, self-evidently, and without proof or argument. Moreover, the idea that “a thing can’t be known until it is scientifically tested” is itself not a scientific idea, for it is neither falsifiable nor empirically verifiable. The atheist’s ideas, therefore, can’t pass their own scientific test. 

Here’s the main point: Not all knowledge, then, needs to be grounded upon proof—especially scientific, empirical proof.

So, I think prior to entering discussions about “God’s existence,” one needs to discuss these issues further. A person must remember that, while science (and the scientific method) is a means to knowledge (we’ve learned a lot about the cosmos with it, after all), it is not the only means to knowledge. Sometimes we know things without “proof” or “argument” at all, as we have seen above. Perhaps knowing God is like this as well. Some philosophers (like Alvin Plantinga from the University of Notre Dame) have taught that belief in God is justified without any argument since it is a “properly basic belief.” And I think I would personally agree with that, though I would like to study more on the subject. Granted this, though, can arguments for God’s existence be helpful to show that God truly exists? Can crafting logical arguments help us see evidence for God’s existence? Can logical reasoning, from premise to conclusion, lead us to belief in God? I most definitely think it can. But that’s a subject for another time.