John Maynard Keynes concluded his magisterial General Theory of Employment, Interest and Money (1935) with these observations about the power and persistence of beliefs:
[T]he ideas of economists and political philosophers, both when they are right and when they are wrong, are more powerful than is commonly understood. Indeed the world is ruled by little else. Practical men, who believe themselves to be quite exempt from any intellectual influences, are usually the slaves of some defunct economist. Madmen in authority, who hear voices in the air, are distilling their frenzy from some academic scribbler of a few years back. I am sure that the power of vested interests is vastly exaggerated compared with the gradual encroachment of ideas. Not, indeed, immediately, but after a certain interval; for in the field of economic and political philosophy there are not many who are influenced by new theories after they are twenty-five or thirty years of age, so that the ideas which civil servants and politicians and even agitators apply to current events are not likely to be the newest. But, soon or late, it is ideas, not vested interests, which are dangerous for good or evil.
Although Keynes did not expect those old enough to hold political power to change their beliefs, he expressed optimism that subsequent generations can and will adopt better ones. In contrast, the quotation from Josh Billings in the subtitle of this blog reflects a frustration with the slowness with which new ideas take hold because of the inability of old dogs to learn new tricks. To a large extent the purpose of this blog has been to confront prevailing beliefs with contrary facts to see what, if anything, would happen. In this post, I speculate a bit on why beliefs are so persistent. [UPDATE 10/15/2010: The Josh Billings quotation, which has been replaced, was "The trouble with people is not that they don't know but that they know so much that ain't so."]
By "belief" I mean any idea we are reluctant to change or re-examine. Such a belief may have been acquired via a rigorous analytical process based on measurements, by received wisdom or folklore, by experience, or in other ways. We may have forgotten the details of how and why we acquired the belief and be unable to explain it to others. A belief may have deep emotional importance such as religious dogma or be devoid of emotional content such as a belief that there are 50 States in the USA or that 8 x 9 = 72. A belief may be true or false, but either way we resist consideration of contrary proofs because we "know" we are right.
Perhaps the tendency to unchanging beliefs has evolutionary advantages, for example:
Aids Learning. Our minds seem to discern, create, and use patterns to see, hear, think, etc., and things that don't fit a familiar pattern are likely to be rejected or distorted. Random facts like nonsense syllables are more difficult to learn and recall than facts that can be anchored to an existing body of knowledge. If a new idea contradicts the existing knowledge, one may have to do a great deal of mental work to reorganize and/or prune old ideas in order to incorporate the new idea.
Constitutes Intellectual Capital. To the extent our beliefs derive from education and experience, they constitute part of our "intellectual capital," which increases our efficiency. We can make more decisions faster if we can plug a few facts into a template instead of having to start anew to solve a problem as though we'd never seen anything like it before. In large part, this is the difference between an experienced lawyer (or other professional) and a newbie. A smart newbie given enough time can perhaps solve any problem that is presented, but the valuable professional is one who already has solved 80% of the problem by having worked through similar situations in the past.
Minimizes the Discomfort of Uncertainty. Perhaps it is stressful to feel confused and in a strange and meaningless situation with no patterns that seem familiar. Perhaps such stress aids survival by keeping us away from situations that may be dangerous because we don't know how to handle them. If gaining knowledge to eliminate that stressful feeling is a deep psychological need, perhaps people would feel better about having an objectively false or foolish belief than about saying to themselves, "I don't know." If so, when a belief is challenged, there is a threat to remove a "security blanket."
Provides Tribal Glue. Beliefs are tribal glue, I think. There is practical value in believing or pretending to believe what people important to us believe, even if such beliefs are entirely false and utterly stupid. Churches are typically upset by heretics in their midst even if they are very tolerant of disbelievers outside the church. Our public beliefs are part of our social identity, and it doesn't matter whether the beliefs are about "facts" or about theory or something that is unverifiable. It may well be difficult to trust or rely on a tribe member whose behavior we cannot predict. Perhaps this social cohesion function explains the odd finding that scientists as a group are very unlikely to believe in God. "Most polls show that about 90% of the general public believes in a personal God; yet 93% of the members of the National Academy of Sciences do not."—Sam Harris here. That doesn't mean scientists function without beliefs. They just have a different set of beliefs including a belief in the sanctity of facts observed in the physical world, that the world is orderly and (eventually) understandable by mortals, and that there are no miracles or interventions by a Supreme Being.
Improves Social Status. Belief may be better than actual knowledge in a contest for leadership of the pack. It's hard to be the leader when you admit you need to study the issue and a rival confidently expresses a belief. A blog comment I read recently on the subject of why very smart economists often publish dumb economic analysis and advice said he was told by a "smirking" professor, that "it's better to be wrong than to be irrelevant."
Reinforces Authority. Beliefs may be useful to maintain hierarchical or social control and discipline. One whose conduct has been inconsistent with orthodox beliefs is not permitted to challenge the correctness of the beliefs. He may argue that his conduct was in fact consistent with the beliefs or reaffirm the beliefs and explain why it won't happen again. On such occasions, Homer says miscreant Greeks blamed "ate," translated as blindness or confusion temporarily thrust upon them by the gods.
Update on Monday, March 1, 2010 at 01:17PM by
Skeptic
Lawrence M. Krauss discusses the function of belief for theoretical physicists in Hiding in the Mirror, Viking Press (2005). After describing the development of theoretical models of the universe that attempt to tie all the known forces of nature, including especially gravity, and quantum theory together into one model that explains everything, Krauss says none of these conjectures has been proven experimentally but that efforts have nevertheless been worthwhile.
It does a disservice to the most remarkable century in the history of human intellectual investigation to diminish the profound theoretical and experimental discoveries we have made in favor of what is at the present time essentially well-motivated, educated speculation. It is also simply disingenuous to claim that there is any definitive evidence that any of the ideas associated with string theory yet bear a clear connection to reality, or that they will even survive in their present form for very much longer. Perhaps more to the point, the deeper we probe these theories, the hazier they seem to have become.
At 247. Krauss goes on, at 247-49 to discuss the role of Edward Witten, who has been the leading force driving string theory since the mid 1980s.”
Ed may be a “true believer” in string theory, but that simply reflects the very nature of his position on the theoretical forefront. It is, as I have stressed, very difficult to devote the incredible intellectual energy and focus that are required over long periods of time in the attempt to unravel the hidden realities of nature if one does not have great personal conviction that one has a good chance of being on the right track. . . .
The same level of personal conviction is required of artists and writers, as well. But what makes science somewhat different, I believe, is that great scientists are prepared to follow an idea for as long as decades, but at the same time are equally prepared to dispense with all of this effort in a New York minute if a better idea or a contradictory experimental result comes along.
Two comments: First, the “belief” discussed by Krauss and attributed to Witten is probably not the belief that the various conjectures are actually and literally truth but perhaps only that they are promising avenues for investigation and that they may very well turn out eventually to have an important element of objective, proven truth in them. However, as Krauss points out at 249, when you talk to some theoretical physicists, their enthusiasm may well sound like belief in “truth.” Second, if Thomas Kuhn is right in The Structure of Scientific Revolutions (1962), then it takes a great deal more than a “New York minute” to dispense with all the work of one’s career. Doing that goes against all six of the reasons for belief outlined in the initial post: Learning the new paradigm is difficult because it doesn’t accrete to the existing body of knowledge. One has to “write down” intellectual capital. One must live with the stress of uncertainty—at least until one adopts as certain a replacement belief. One tends to lose his/her tribal affiliations (unless the whole tribe migrates together from old belief to new belief). One is likely to suffer diminution of social status and authority because others will have greater expertise in the new paradigm and will be perceived as having been "right" instead of "wrong."