day had become so mechanized that if on entering the room I had been
asked whether on that particular day I had really unlocked the door, I
could not have told. The train took care of itself and I was not
concerned in it sufficiently for remembrance. Yet it remained my act.
On one or two occasions, after shoving in the key in my usual
unconscious fashion, I heard voices in the room and knew that it would
be inappropriate to enter. Instantly I stopped and checked the
remainder of the train. Habitual though the series of actions was, and
ordinarily executed without conscious guidance, it as a whole was
aimed at a definite end. If this were unattainable, the train stopped.

All are aware how large a part is played by such mechanization of
conduct. Without it, life could not go on. When a man walks to the
door, he does not decide where to set his foot, what shall be the
length of his step, how he shall maintain his balance on the foot that
is down while the other is raised. These matters were decided when he
was a child. In those infant years which seem to us intellectually so
stationary, a human being is probably making as large acquisitions as
at any period of his later life. He is testing alternatives and
organizing experience into ordered trains. But in the rest of us a
consolidation substantially similar should be going on in some section
of our experience as long as we live. For this is the way we develop:
not the total man at once, but this year one tract of conduct is
surveyed, judged, mechanized; and next year another goes through the
same maturing process. Not until such mechanization has been
accomplished is the conduct truly ours. When, for example, I am
winning the power of speech, I gradually cease to study exactly the
word I utter, the tone in which it is enunciated, how my tongue, lips,
and teeth shall be adjusted in reference to one another. While
occupied with these things, I am no speaker. I become such only when,