What is the argument from reason?

Answer

The argument from reason aims to demonstrate that belief in naturalism is unjustified; it is a belief that cannot be trusted. This is achieved by illustrating that belief in naturalism contradicts confidence in human reason. This is a crucial point, as atheists often try to present their worldview as “more reasonable” than one embracing transcendent ideas. A basic statement of the argument from reason would be:

Either “reason” is simply an illusion of physics—meaning there is no basis for relying on it to form accurate beliefs—or “reason” transcends the physical realm, in which case naturalism is false. If human reason is a product of random particle interactions, it may not lead to truth. Believing that reason leads to truth conflicts with the idea that reason is solely determined by physical processes.

An even more succinct way to put it would be “the existence of reason itself refutes naturalism.”

When discussing philosophical concepts, precise definitions are crucial. In this context, reason is the capacity of the mind to deduce and conclude logically. In the argument from reason, reason denotes using intellect to arrive at genuine, accurate conclusions. Naturalism posits that everything can be explained by physical elements; it asserts that reality consists solely of matter and energy.

Philosophy distinguishes between the queries “how do we ascertain truth?” and “what constitutes reality?” These are respectively known as epistemology and metaphysics. The argument from reason pertains to epistemology: it specifically examines how we acquire knowledge and the extent to which we trust an idea.

Given that reason is integral to our comprehension, the argument from reason strongly implies a metaphysical assertion as well. If “reason” is objectively valid—if reason is a universal principle that transcends the physical—then it points towards a reality beyond the mere physical realm.

Is reason “real”? If so, naturalism would have to be considered “unreal.” If reason does not exist, why did humanity come to perceive it as we do: as a non-material, yet real entity? If light did not exist, we would never realize we were in darkness; in fact, contemplating such a notion would be meaningless. Nevertheless, we differentiate between reason and irrationality.

The argument from reason comprises various arguments, presented in different forms, by both believers and non-believers. Thinkers like Victor Reppert, C. S. Lewis, G. K. Chesterton, and Thomas Nagel have been linked to these assertions. Each argument possesses its own merits and drawbacks, yet they all revolve around a common concept. Proposing that everything in the universe is essentially random implies that one’s own thoughts and conclusions are equally unreliable. One does not necessarily need to adopt—or conclude with—a biblical perspective to recognize the logical potency of this concept.

A notably renowned iteration of the argument from reason was popularized by Alvin Plantinga: the evolutionary argument against naturalism (EAAN). Plantinga highlights that evolution is steered by the survival of the “fittest,” yet beliefs more “fit” for survival may not align with those that are “true.” Hence, if evolution holds true, belief in naturalism lacks justification. In essence, belief in naturalism logically contradicts itself, courtesy of evolution.

To illustrate the evolutionary argument against naturalism, envision an extreme scenario: a man develops an intense desire to be devoured by an invisible bear. This compels him to seek out places where he perceives no bears. This belief goes against survival—not to mention being peculiar—but more significantly, it is factually incorrect. His rationale did not lead to truth, as invisible bears do not exist. Nonetheless, this bizarre, erroneous reasoning enhances the man’s survival chances by prompting him to steer clear of visible bears; that is, those he can see.

This demonstrates how “that which is good for survival” is not identical to “that which is true.” It is entirely possible for human reasoning to be significantly incorrect and still yield “advantageous” results from a survival or evolutionary standpoint. If human reason is solely the outcome of purposeless, survival-driven evolution, then “useful” reasoning and “truthful” reasoning are separate categories. This implies that all outcomes of human reason are unreliable, including belief in naturalism and evolution.

This brings us back to the fundamental assertion of the argument from reason: one can have faith in naturalism or rely on reason, but one cannot do both. The conflict may appear trivial when applied to practical issues, but the more abstract the concept is—such as with ideas like naturalism—the less certainty one can have in the truthfulness of human reason.

The most common effort to disprove arguments from reason involves the concept of emergence. This suggests that certain concepts arise from—the combined interaction of less complex elements. Naturally, in a naturalistic worldview, emergent is equivalent to highly complex. Either the entire process fundamentally relies on basic physics, or it does not. If the process does not reduce to matter and energy, then it is not naturalistic. Another frequent mistake is to argue that discrediting a single version of the argument from reason somehow validates naturalism. This is, paradoxically, irrational, as proving that a conclusion was reached illogically does not, by itself, indicate the conclusion is untrue.

Like most such concepts, the argument from reason has its limitations. Its aim is to propose an irreconcilable contradiction between the statements “I believe naturalism is true” and “I trust in human reason.” In essence, these arguments do not address the existence of any specific deity. Nor do they offer much insight into the nature of God or the Bible. That being said, the argumeA logical argument from reason is a valuable tool that illustrates how individuals who deny God—such as naturalists—are essentially engaging in irrationality and obstinacy (Romans 1:18-25; Jude 1:10).