#simplicity prior

[tetraspace-west]

confused about the simplicity prior

From what I have heard of the simplicity prior, you assign probability 2^(-L) to each description of length L being the one that describes the environment. For each length L, there are 2^L possible descriptions of that length.

So the total probably you assign to all hypotheses is sum(2^(-L) * 2^(L)) = sum(1) = unnormalisable.

What am I missing?