Less Wrong is a community blog devoted to refining the art of human rationality. Please visit our About page for more information.

Benoit_Essiambre comments on Avoiding Your Belief's Real Weak Points - Less Wrong

50 Post author: Eliezer_Yudkowsky 05 October 2007 01:59AM

You are viewing a comment permalink. View the original post to see all comments and the full post content.

Comments (205)

Sort By: Old

You are viewing a single comment's thread.

Comment author: Benoit_Essiambre 06 October 2007 03:45:59AM 0 points [-]

I call myself an atheist. However, I actually think believing in a vague god is based on probabilisticly rational and bayesian kind of thinking, at least for the limited context humans live in.

I say 'vague god' because I believe most people who believe there is a god and have somewhat solid arguments supporting this fact often use fallaciously the wrong level of conceptual abstraction to support their _own_ specific god. The word god is not very well defined and there is quite a large margin around the definition to play with. I find the best arguments, like the prime-mover or entropy argument, are bayesian in a certain context but even where they make sense, they prove nothing but a very vague god. Theists have a very annoying tendency to use these arguments, which in reality, only support the fact that there is 'something' that somewhat fits the definition of "god" (in that it is a creator) that is complex enough to have 'created' the universe (assuming the concept of 'creation' makes sense outside the universe), or at least something which created the thermodynamic order found in the universe. There is never any good evidence for the specific gods, only for some vague god that is probably more similar to a physical phenomenon like the big bang than to the gods of religious literature.

Now why do I think the vague gods are, in some sense, rational ? It came to me while I was thinking about bayesian probabilities, while reading Jaynes book. In most problems, propability is conditioned on some variable I, representing general contextual knowledge. The equations often take the form of P(H|O,I) which represents the probability of an hypothesis H knowing some observations O and other more general facts 'I'. Jaynes never said much about 'I' except that it is whatever else we know about the problem. I like to think of 'I' as a sort of low enthropy bounded context. I sometimes call it the 'contextual urn' because probability texts often idealise this information into an urn. The contextual urn need not have a hard boundary like a real urn, its bounds can be empty space as distance itself or even time can isolate things in the universe. (As an aside, I think studying how we recognise these contexts and their bounds could explain a lot about how we reason and how to make predictions about the universe. It is a hole in probability theory which needs to be understood before we can build Jaynes rational robot) 'I' is some recognisable context that allows us to make predictions. The fact that it is recognisable means it has properties that we have seen before. The contextual urn defines a sitation, a spacio-temporal region, that is low entropy enough to be recognisable and that repeats itself often enough that we can learn things about it.

The next thing I noticed about the relationship between 'I', 'O' and H is that we can kind of view 'I' and O as a cause of H and effects seem never to be more complex than their causes. This is particularly true about creation as far as we can take a creator and his creation to be a cause and effect (Which philosophers like Hume accepted). Taking an information theoretic perspective, if something can create someting else, it contains all the information to create it and probably more. It is at least as complex entropically as the thing it creates. Humans have always lived in a world where this was true almost all the time and hence it is perfectly reasonable for them to deduce using bayesian reasoning that's how things pretty much always work. It is not hard to see then that living organisma, humans or even the universe in general contain a great amount of complexity and there has to be something even more complex which created them. e.g. god.

If we look further than our immediate existence, we find out that it is not always true that a cause is more complex than its effect. Because of random variations, an effect is not very probable to be more complex than its cause but _it CAN happen_ sometimes. And as a result of natural selection, it is possible for the complexity of populations of effects to increase given a bias which makes the more complex survive more than the less.

Evolution is not something that happens in the time-scale of a human life therefore it is not very useful to us. We thus have evolved and rationally learned during our lifetime that effects are probably _always_ less complex than their causes. And in the context of a relatively short life span this is right!

We have to look at a wider timespan to see that there is actually another way for complexity to arise and that it explains the complexity we observe much better than the gods of religions. This is of course the theory of evolution.

I think this explains why theists feel so threatened by evolution. It's because it is the only good alternative for the creation of complexity. And although most people don't understand the principles of entropy and thermodynamics, most people's innate Bayesian reasoning leads them to the right conclusions: When they see the alternative explaining the creation of complexity and when they see how well the theory of evolution fits historical evidence, their last argument for the belief in god vaporises.