and in showing this, still more will appear. It will appear that
it was the lengthening of infancy which ages ago gradually
converted our forefathers from brute creatures into human
creatures. It is babyhood that has made man what he is. The
simple unaided operation of natural selection could never have
resulted in the origination of the human race. Natural selection
might have gone on forever improving the breed of the highest
animal in many ways, but it could never _unaided_ have started the
process of civilization or have given to man those peculiar
attributes in virtue of which it has been well said that the
difference between him and the highest of apes immeasurably
transcends in value the difference between an ape and a blade of
grass. In order to bring about that wonderful event, the Creation
of Man, natural selection had to call in the aid of other agencies,
and the chief of these agencies was the gradual lengthening of
babyhood.

Such is the point which I wish to illustrate in few words, and to
indicate some of its bearings on the history of human progress.
Let us first observe what it was then lengthened the infancy of the
highest animal, for then we shall be the better able to understand
the character of the prodigious effects which this infancy has
wrought. A few familiar facts concerning the method in which men
learn how to do things will help us here.

When we begin to learn to play the piano, we have to devote much
time and thought to the adjustment and movement of our fingers and
to the interpretation of the vast and complicated multitude of
symbols which make up the printed page of music that stands before
us. For a long time, therefore, our attempts are feeble and