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JoshuaZ comments on [Link] The Bayesian argument against induction. - Less Wrong Discussion

4 Post author: Peterdjones 18 July 2011 09:52PM

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Comment author: JoshuaZ 19 July 2011 03:17:49AM 6 points [-]

Interesting but extremely unpersuasive.

I agreed with everything up until this point:

That is, to the extent that B increases the probability of A, it does so by increasing the probability of A v B more than it decreases the probability of A v ~B. However, since A v B is a logical consequence of B to begin with, the increase in probability is a purely deductive inference.

This seems to be wordgames. Saying this is a deductive inference misses the whole point that this an inference which can only be used after B has been observed. Otherwise it is just math.

The next paragraph seems to be similarly flawed.

The inductive view of probabilistic inference rests on the fallacy of decomposition, i.e. assuming that what is true for the whole must be true for its parts. Not only do logical consequences of A which are independent of B not increase in probability, they may actually decrease in probability.

Here I may just be missing the point but I don't see how logical consequences of A are relevant to the issue of whether induction is occurring.

I have to wonder if some strange notion of induction is occurring where intuitions are simply not shared. I wonder, what would happen if we tabooed induction?