March 23, 2007
Why belief in god is irrational
In yesterday's post I argued that there are conditions under which it is not irrational to believe in things for which there is no evidence at all. The example was given of extra-terrestrial life or space aliens. Since the universe is very large and very old and we know contains a vast number of galaxies, there exists a plausible argument that life, even intelligent life, could exist elsewhere in the universe that we are unaware of.
But believing in other things, such as that space aliens are buzzing around us mysteriously all the time or that dragons and unicorns and the like are roaming in some secret regions of the Earth, is irrational because to retain such beliefs requires one to create very complicated and implausible scenarios to explain the absence of any evidence in favor of them.
Similarly, the idea that that there exists an afterlife is also irrational because having that belief requires one to construct a whole superstructure of auxiliary beliefs in order to sustain that belief, and these auxiliary beliefs are themselves implausible and not supported by evidence and also depend on some kind of willful attempt at concealment of evidence, so one ends up building a whole house of cards of implausible theories just in order to sustain that one belief.
What about belief in god? Is that rational or irrational? Some have argued that it is no harder to believe in a god than that there is intelligent life elsewhere in the universe, since both have no convincing evidence in support of the belief.
But with god, the kinds of explanations for the absence of evidence that can rescue intelligent extra-terrestrial life and place it in the realm of rationality no longer apply. The problem is caused by the very qualities that religious people ascribe to god. With intelligent extra-terrestrial life, we assume that they, like us, are limited by space and time and the laws of nature. In particular, they cannot travel faster than the speed of light, which puts a real crimp on being able to get around this vast universe. After all, even if their technology was so advanced that they could travel at speeds approaching the speed of light, it would still generally take years for them to reach even the nearest neighboring star, so exploring beyond their our own galaxy becomes an enormously time consuming activity. So believing that there exists intelligent life in some remote part of the universe that is so far inaccessible to us is not an outlandish belief because the auxiliary beliefs that are necessary to sustain it (such as a very large universe and limits to travel) are supported by evidence. So the Raelians actually have a more plausible belief structure than mainstream religions.
If (hypothetically) the universe was quite small and could be traversed in a brief time, and people started invoking ideas like that extraterrestrial life existed but they were deliberately and cleverly hiding from us, then that belief starts becoming irrational.
But in the case of god, he/she is not supposed to be not limited by space and time. He/she can be everywhere all the time and has infinite powers to boot. So there is no reason at all why god should not be able to provide us with the kind of convincing evidence that I outlined earlier that would remove all doubts once and for all.
In order to overcome this problem, religious believers have to construct auxiliary hypotheses, similar to the ones that become necessary to sustain a belief in the afterlife. It is postulated that god does not want to be seen by us and has the ability to stay hidden, choosing to be seen in highly selective situations, although those situations seem to be becoming increasingly trivialized and bizarre, such as appearing in grilled cheese sandwiches, damp spots in highway overpasses, and the like.
In such situations, the absence of convincing evidence casts serious doubts on god's existence and lifts the belief in god into the realm of irrationality. However, the faithful continue to remain devout. It does not seem that they wonder why god goes to all that trouble to provide just tantalizing glimpses. Those who do wonder about this have to, at this point and as a last resort, invoke the inscrutability argument: We cannot presume to understand why god does these things, we just have to believe that there is a good reason that is being hidden for us.
I think that this could be used as a test as to whether a belief that is sustained in the absence of evidence is rational or irrational:
• For a belief to be irrational, in order to sustain it one must argue for the existence of something that is in principle unknowable and also requires a deliberate scheme to conceal evidence of existence.
• For a belief to be rational it needs to be something that is unknown only in practice due to limitations of time or technology, but may become known in the future, and the absence of evidence is not due to willful deception by the very entity whose existence we seek.
This is not how most people seem to view rationality. People tend to view a belief is rational simply because a large number of people believe in it and if it has been around for a long time. But those two arguments really have no merit since it is quite possible for large numbers of people to believe false things for a long time.
But numbers and time seem to be the only thing that belief in god has going for it.
POST SCRIPT: Famous atheists
It contains scientists (Albert Einstein, Charles Darwin), writers (Ernest Hemingway, Leo Tolstoy), popular culture celebrities (Angelina Jolie, Woody Allen), political figures (Abraham Lincoln, Susan B. Anthony), and even people who are not famous (me).