Do We Have a Moral Obligation to be Rational?

Before proceeding to discuss Clifford’s better points (in my next essay), I shall here discuss an aspect of his perspective with which I entirely disagree. He argued that our duty to base our beliefs on evidence and not to deliberately ignore or suppress evidence that may call our beliefs into question is ultimately a “duty to mankind.” No person’s belief “is in any case a private matter which concerns himself alone.”

This is far too grandiose and altruistic for my tastes. For one thing, human language was not “created by society for social purposes.” Society does not, because it cannot, create anything. All of our moral obligations are to particular individuals, not to an abstraction called “society”; and we have no inherent moral obligations to other people beyond respecting their rights. Moreover, natural languages (in most respects) evolved over time to suit the purposes of individuals, not to benefit society as a whole. True, we do benefit greatly from the “modes of thought” from previous generations, but here our gratitude must be selective. We have inherited both good and evil modes of thought. Theories of persecution and totalitarianism are as rife in the history of ideas as are theories of toleration and freedom. It would be absurd to view earlier beliefs that defend persecution and totalitarianism as “a precious deposit and a sacred trust” that we should preserve and transmit to future generations.

But let’s give Clifford his due. It is clear that he would have agreed with my claim that bad ideas from the past should be rejected, so perhaps I have not correctly understood his point. Referring to two previous hypotheticals he had used to illustrate his thesis, Clifford wrote:

This is a difficult argument to buy. Many beliefs, however irrational they may be, are so trivial as to have no effects on other people at all. A lonely, isolated old woman may believe that her cats understand everything she says, and this would certainly qualify as “self-​deception,” as Clifford understood the term. But I cannot see how this bit of self-​deception (and many more like it) has any “effect on the fate of mankind.” How would it benefit humankind if we could persuade the old woman to accept a more rational view of cats? And what would we think of a person who went out of his way to convince the old woman that her belief is wrong, that her cats don’t understand her at all so it is pointless to talk to them? There are times, I think, when it is more humane to leave a harmless irrational belief undisturbed, rather than attempt to convince a person that her treasured belief lacks sufficient justification. For one thing, what a person believes may be none of our business.

Clifford continued:

There is a streak of elitism in this passage. How should we judge the downtrodden medieval serf who worked fourteen hours a day to feed his family, who was unable to read or write, and who accepted orthodox Catholicism, as taught to him by his parish priest? Should we condemn him for defaulting on his “duty” to mankind by failing to question his religious beliefs? In fact, a good deal of religious skepticism—at least about orthodox Christian beliefs—is found among the lower classes in medieval Europe, so we should not suppose that peasants were unable to think for themselves. But even here the belief in magic—a remnant of old paganism—was extremely common.

We must understand the function that a belief system plays in a person’s life. First and foremost a belief system provides coherence—a conceptual framework that enables a person to make sense of the world. Belief systems that we regard as irrational today, such as the rituals and magical practices of primitive tribes, served this purpose in many early cultures around the world; and it would be highly unreasonable to criticize those cultures, which lacked any knowledge of natural science, for embracing and perpetuating irrational beliefs. Belief systems are similar to what Thomas Kuhn called a normal paradigm in science. A normal paradigm, whether in science or more generally, will have a presumption in its favor and will not be overthrown until it is unable to explain a significant number of phenomena. And even here changes may not occur until older, conventional thinkers are displaced by a new generation that is not committed to the prevailing belief system.

Generally speaking, an entrenched belief system will be challenged only by innovative and independent thinkers, not by the masses. And even some of these original thinkers may be “sleepwalkers” in Arthur Koestler’s sense of the word. That is to say, the authentic insights and discoveries of great thinkers may be intermixed with many false beliefs, as we find with the astronomical discoveries of Kepler, which were used to support his mystical belief in astrology. It was left to later scientists to separate the wheat from the chaff in Kepler’s theories. This is the way knowledge advances.

The essential point is this: true beliefs and justified beliefs are not the same thing. Many justified beliefs – propositions that were quite reasonable to believe in a particular context – have been revised or rejected altogether in the light of new knowledge. A good example is the Copernican revolution in astronomy, which was followed by Kepler’s rejection of circular orbits. The medieval cosmology – an eclectic brew of Aristotelian physics, Neoplatonic metaphysics, and Ptolemaic astronomy—may be dubbed rational (to a point) given the medieval context of knowledge and the best evidence that was then available. It was supported by a long-​established and coherent theory of metaphysics, was defended for centuries by the best scientific minds, and was quite adequate for explaining the available astronomical data (prior to the more precise observations of Tycho Brahe). But that cosmology was incorrect nevertheless.

Here it is important to differentiate moral beliefs from beliefs about physical nature. If we agree that thirteenth-​century philosophers should not necessarily be dubbed “irrational” for holding beliefs about the universe that were subsequently discarded as false, should we say that same about the common moral belief (held by Thomas Aquinas and many theologians) that obstinate heretics should be put to death? No, for consider the difference. Advances in scientific knowledge are impossible without previous advances in knowledge to build upon. Scientific knowledge is cumulative, so it would be foolish to condemn Aquinas for his ignorance of Einstein’s theory of relativity. But the same is not true of the moral issue of persecution of heretics, for many Christians, going to back to the early Christian era, clearly understood that persecution is wrong and inconsistent with the teachings of Jesus. It is not as if the case for religious toleration was unheard of in the thirteenth century; indeed, it preceded by at least three centuries the development of the theory of persecution. (See my essays Augustine’s Case for Righteous Persecution and Notes on Persecution and Toleration in the History of Christianity.) Hence the theory of relativity was not an option for Aquinas, but a defense of religious toleration certainly was. (May we speak of a progress in moral knowledge as we speak of a progress in scientific knowledge? This problem was widely discussed by classical liberals, especially during the nineteenth century, but I shall have to postpone offering my opinion until some point in the future.)

As noted above, my next essay will consider some of Clifford’s points about the ethics of belief that strike me as more credible than his claim that our duty to be rational is principally a duty, or moral obligation, we owe to mankind. If there is any moral obligation involved here, it is a moral obligation to ourselves.