Rational Animal

Aristotle defined humans as the rational animal. In recent times it has been argued that other animals are also rational. As always with any concept, it depends on how you analyze “rational.” But let us suppose for the moment that there is a sense of “rational” that only humans possess. There is still an ambiguity in meaning, I submit. I think there are at least two ways in which a human being might be considered rational … and hence also irrational … and this is often missed.

            One way that we are rational, and perhaps the standard notion, is that we have the capacity to think logically. It seems pretty clear that we (and for that matter all organisms) must have a pretty intuitive grasp of what follows from what, since mere instinct or habit does not account for all of the countless adjustments an individual makes in the course of the day in order to accomplish mundane tasks, not to mention stay alive. Novel situations confront us at every turn, and so we must reason from the familiar to the less familiar. So for example, while instinct may cause us to duck when we see an object hurtling toward us, and habit to deposit our paycheck in the bank, it takes some reasoning to decide or be motivated to try to stop smoking if you read about the illnesses it can cause.

            All of us are also irrational in this sense to some degree. We do stupid things because we have reasoned fallaciously, by making a mistake either of pure or formal or deductive logic or of informal or inductive logic.

An example of the former:

Fish live in the sea.

Whales live in the sea.

Therefore whales are fish.

An example of the latter:

It says on the Internet that there are cannibals in the White House.

Therefore there are cannibals in the White House.

But presumably these are local or episodic errors, due to our being rushed or distressed or tired, and do not change the fact that, by and large, we have the capacity to think (and hence act) logically and usually do.

But suppose that someone were rational in the above sense, that is, logical, albeit fallibly, in their thinking. They might still be irrational in another sense, to wit: Someone may not value rationality. I think I know people like this. They are as rational as you or I am in their logical capacity, but they do not exercise that capacity reliably -- not due to stressed conditions that induce errors but because, frankly, they don’t give a damn (about being rational) … or, in the extreme case, might even be doctrinally opposed to it.

I chose “doctrinally” deliberately, since one quite commonly comes across the intentional abandonment of reason in the context of religion. Specifically there is the doctrine that faith is a separate domain from reason, so that when it comes to certain propositions, one is urged to rely on faith even if the propositions appear to fly in the face of reason. Perhaps the most fundamental example of this is the proposition that the universe was created and is ruled by a God who is perfectly good (and all-knowing, and omnipotent). Yet if one were to consider the evidence and reason therefrom, one could not possibly lend the slightest credence to that proposition. (This is known as the Problem of Evil.) So we are told that God works in mysterious ways, and this must be accepted on faith. Well, it is certainly logical to conclude that the only way to accept the original proposition is by faith, which is to say, irrationally. But it is hardly rational to therefore accept the proposition on faith! And since it cannot be accepted on the basis of sound reasoning either, the rational conclusion would be that it is most likely false.

But my point herein is only that people who do nevertheless accept things “on faith” are irrational in a distinct sense from those who are irrational because they are unable to reason logically. Most religious believers are perfectly rational in the primary sense, but for some reason (that is, cause,* whether it be sheer habit due to upbringing, or extreme wishful thinking due to crisis or hardships, etc.) – they carve out a domain where they explicitly rule out rationality as the basis for accepting or rejecting propositions.

In sum, then: We are rational animals, but some of us are consistently rational in only one of two senses. Any normally functioning adult human is capable of thinking logically and often does, and so is rational in the primary sense. But to be fully rational (again, allowing for the occasional error) means also to value rationality in all of the important domains of life. It may be that only a minority of human beings are rational in this sense. 

* It is certainly possible that some religious believers, or other persons, forswear rationality for a reason, that is, on rational grounds. For instance, a person could reason inductively that her fervent and competent efforts to be rational have led to nothing but misery for herself and others, whereas the irrational believers she knows tend to lead happy and fruitful lives; so it could make sense for her to set rationality aside to some degree or in some spheres of life.