Also every mutations has an effect, even if it is very very very small. So truely neutral mutations don't exist.
An irrelevant argument. Even if this is true, in a finite population, mutations that are only slightly deleterious (specifically if the selection coefficient against it is less than the reciprocal of twice the effective population size) are effectively neutral and not exposed to selection.
We have many intuitions in our life and the point is that many of these intuitions are wrong. The question is, are we going to test those intuitions?
-Dan Ariely
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