this it is a sign that we have already involuntarily seen or heard
more than we wished. The familiar, whether sight or sound, very
commonly escapes us.

Take again the processes of digestion, the action of the heart, and
the oxygenisation of the blood--processes of extreme intricacy, done
almost entirely unconsciously, and quite beyond the control of our
volition.

Is it possible that our unconsciousness concerning our own
performance of all these processes arises from over-experience?

Is there anything in digestion, or the oxygenisation of the blood,
different in kind to the rapid unconscious action of a man playing a
difficult piece of music on the piano? There may be in degree, but
as a man who sits down to play what he well knows, plays on, when
once started, almost, as we say, mechanically, so, having eaten his
dinner, he digests it as a matter of course, unless it has been in
some way unfamiliar to him, or he to it, owing to some derangement or
occurrence with which he is unfamiliar, and under which therefore he
is at a loss now to comport himself, as a player would be at a loss
how to play with gloves on, or with gout in his fingers, or if set to
play music upside down.

Can we show that all the acquired actions of childhood and after-
life, which we now do unconsciously, or without conscious exercise of
the will, are familiar acts--acts which we have already done a very
great number of times?

Can we also show that there are no acquired actions which we can