Only because we are so familiar with the great phenomenon of causality
do we take it for granted, and think that we reach an ultimate
explanation of anything when we have succeeded in finding the 'cause'
thereof: when, in point of fact, we have only succeeded in merging it in
the mystery of mysteries. I often wish we could have come into the
world, like the young of some other mammals, with all the powers of
intellect that we shall ever subsequently attain already developed, but
without any individual experience, and so without any of the blunting
effects of custom. Could we have done so, surely nothing in the world
would more acutely excite our intelligent astonishment than the one
universal fact of causation. That everything which happens should have a
cause, that this should invariably be proportioned to its effect, so
that, no matter how complex the interaction of causes, the same
interaction should always produce the same result; that this rigidly
exact system of energizing should be found to present all the
appearances of universality and of eternity, so that, e.g., the motion
of the solar system in space is being determined by some causes beyond
human ken, and that we are indebted to billions of cellular unions, each
involving billions of separate causes, for our hereditary passage from
an invertebrate ancestry,--that such things should be, would surely
strike us as the most wonderful fact in this wonderful universe.

Now, although familiarity with this fact has made us forget its wonder
to the extent of virtually assuming that we know all about it,
philosophical enquiry shows that, besides empirically knowing it to be a
fact, we only know one other thing about it, viz.--that our knowledge of
it is derived from our own activity when we ourselves are causes. No
result of psychological analysis seems to me more certain than this[47].
If it were not for our own volitions, we should be ignorant of what we
can now not doubt, on pain of suicidal scepticism, to be the most