Kant says that all our knowledge is founded on experience. But each new
small increment of knowledge is not so founded, and our whole knowledge
is made up of the accumulation of these small new increments not one of
which is founded upon experience. Our knowledge, then, is founded not on
experience but on inexperience; for where there is no novelty, that is to
say no inexperience, there is no increment in experience. Our knowledge
is really founded upon something which we do not know, but it is
converted into experience by memory.
It is like species—we do not know the cause of the variations whose
accumulation results in species and any explanation which leaves this out
of sight ignores the whole difficulty. We want to know the cause of the
effect that inexperience produces on us.