Are Faith and Reason Irreconcilable?

It is not unusual in today’s postmodern world to hear people criticize the idea of “binaries”—the idea that things can be classed into two distinctive groups. The distinction between males and females, right or wrong, beautiful and ugly, true or false—all of these distinctions are now to be interrogated and seen as questionable.

And, of course, there are those who point out that the people who are opposed to thinking in binaries can be distinguished from people who don’t oppose such thinking, which implies that there is at least one binary—that between people who oppose binaries and people who don’t.

In the long history of human thought there has been much discussion about two things that have often been categorized as binaries: faith and reason. There are many people who think that these two things are irreconcilable. Are they right?

Let’s first define our terms. What do we mean by “faith” and “reason”?

By the term “faith” we usually mean a sentiment of belief or trust. When I say, “I believe in him,” it means I trust the person, usually based on what is already known about his character. But most often we use the term “faith” to refer to the religious faith we have in God. This is often how the word is used in the Bible. As Mortimer Adler once pointed out, “In the Old Testament, the term ‘faith’ has the sense of absolute steadfastness, assurance, and loyalty.” The word “faith” does not refer to anything we can empirically prove or be certain about. We do not know that the person is as good or trustworthy as we think, or that God is God, but we believe.

The philosopher Søren Kierkegaard is famous for having characterized faith as a “leap.” This has given us the expression “leap of faith.” This conception of faith has been the cause of so many people considering faith to be a merely subjective thing, opposed to reason. We often think of the “leap of faith” as something irrational: We have to “leap” because reason won’t take us where we want to go.

The word “reason” also has several connotations. They range from the more strict sense of formal logic to the broader idea of common sense. This range of meanings can be seen in the way we use words like “rational” and “irrational.” Often we characterize someone’s action as “irrational” when what we really mean is that the action violates common sense. And other times we mean it in the sense of being technically illogical. But if we think of the word “reason” in a sort of middle sense—one in which it refers to beliefs that are generally grounded in logical thinking and respect for evidence—then we have the sense in which it is used in expressions like “faith and reason.”

Clearly these two terms—”faith” and “reason”—refer to two different things. “Faith” relies on belief in unknowable things, and “reason” depends on knowing certain things. But are they irreconcilable, as some people seem to think? Let’s see if there is a way the two can come together, first by approaching reason from the point of view of faith, and then by approaching faith from the point of view of reason. We’ll come at it from two opposite directions to see if, in fact, they are in opposition.

So, let’s start from the most subjectivist view of faith—the idea of faith as a “leap”—and see how far toward reason we can get. We could ask the question: “What is the leap from and where is it to?” In other words, when we leap from, say, a dock to a boat floating on the water a few feet away, we are going from one place or thing (the dock) to another (the boat). If we think carefully about this, we realize that faith is a leap from probability to certainty.

When I consider jumping from the dock to the boat, I believe that I have a high probability of getting to the boat without falling in the water. But when I actually jump to the boat I leap, so to speak, from the level of probability I have of doing it successfully (let’s say 95%) to the certainty I have once I have reached the dock (100%). The difference between the probability and the certainty (the remaining 5%) is faith, and it is only by exercising it that I am able to get onto the boat.

In this respect, faith is a necessary element in any decision. Very few decisions involve certainty. Most involve a level of uncertainty that must be bridged. In religious terms, most of us are certain that God exists in the philosophical sense. But other than a few arguments that are understandable only by experienced philosophers, there are no logically demonstrable proofs of His existence. There is always a gap between what we, as human beings, can know about God and what we believe about God.

From the perspective of reason, if we take reason in its more strict sense—that of deductive logic—we realize very quickly that logic itself requires faith to operate at all. The basic rules of logic (and this would be the case with geometry as well) are based on assumptions which cannot themselves be proved. You can’t prove the truth of the law of non-contradiction, which is the central assumption of all logic: Saying “Logic is true” and “Logic is not true” cannot both be true at the same time in the same respect. There is no way to prove the law at all. You take it on faith.

But logic alone will not get us very far. If we stay in the realm of geometry, then logic is all we need. We have some axioms which we simply posit, and we use logic to infer all of our conclusions. There are also certain branches of philosophy (such as metaphysics) that are similar. And there are aspects of physics which, being almost purely mathematical, rely very little on anything outside of the certain truths of math.

But most of the rest of the truths of this world are not this way. The natural sciences are a good example.

When we employ inductive or scientific reasoning, we look at all the specific cases of certain occurrences—say, the fact that bodies with mass exercise an attraction to each other. We then conclude that there is a “law” of gravity. It is operative in every observation, always. We then say that all objects with physical mass “obey” this law. But have we seen every case of objects with mass and how they behave toward each other at all times? Of course not. Induction simply convinces us to take it on faith that all the cases we haven’t observed are the same as the ones we have observed. In this sense, every scientific experiment is a leap of faith.

We know at one and the same time that faith is the “substance of things hoped for, the evidence of things not seen” (Hebrews 11:1) and that we should be able to give “a reason of the hope that is in [us]” (1 Peter 3:15).