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Old 08-06-2011, 07:24 AM
unreasonable unreasonable is offline
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Quote:
Originally Posted by Skoshi Tiger View Post
No, your statement is an argument that the universe is finite. If the universe is truely infinte then every possiblity no matter how small must be otherwise it would be impossible and not part of the equation.

In an infinte universe an exact copy of you is (or will or has been) trying to convince a copy of me that the universe is infinite and I've just told you that your logic is flawed. Even if there is a 1 in infinity chance of it happening then it will.
Put it another way, your argument is the same as saying that if A is possible, then A must be true. But this is obviously nonsense - possible existence does not mean the same as necessary existence. Possible existence implies the possibility of non-existence. So given that you have derived a contradiction, you either have a false premise or have made a false step of logic (or both!)

We find the mistake easily: if you take some estimated finite probability of, say, life on another planet, or clones of us having this argument on another planet, and multiply by infinity, the answer is not one, but infinity. And an infinite probability has no meaning - a probability cannot exceed 1.

You can only get 1 in your argument by assuming that the probability is 1/infinity to get the equation 1/infinity X infinity/1 = 1 which is trivial.

If you want to have a universe where all sorts of bizarre things are happening you would be better of believing that the universe is not infinite, but very very large, since you can then multiply your prior probability by a large number and then at least get a meaninful answer.

If you like thinking about these sorts of things you might consider reading up about the Bayesian concept of probability, which focuses on probability as the subjective assessment of available evidence, rather than the objectivist concept you appear to use.
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