You know, one of the really weird things about us human beings [...] is that we have somehow created for ourselves languages that are just a bit too flexible and expressive for our brains to handle. We have managed to build languages in which arbitrarily deep nesting of negation and quantification is possible, when we ourselves have major difficulties handling the semantics of anything beyond about depth 1 or 2. That is so weird. But that's how we are: semantic over-achievers, trying to use languages that are quite a bit beyond our intellectual powers.
via Language Log » Never fails: semantic over-achievers