player may have been exercised--to an infinitesimally small extent--
but still truly exercised--on as many as ten thousand occasions
within the space of five minutes, for no note can be struck nor point
attended to without a certain amount of attention, no matter how
rapidly or unconsciously given.

Moreover, each act of attention has been followed by an act of
volition, and each act of volition by a muscular action, which is
composed of many minor actions; some so small that we can no more
follow them than the player himself can perceive them; nevertheless,
it may have been perfectly plain that the player was not attending to
what he was doing, but was listening to conversation on some other
subject, not to say joining in it himself. If he has been playing
the violin, he may have done all the above, and may also have been
walking about. Herr Joachim would unquestionably be able to do all
that has here been described.

So complete would the player's unconsciousness of the attention he is
giving, and the brain power he is exerting appear to be, that we
shall find it difficult to awaken his attention to any particular
part of his performance without putting him out. Indeed we cannot do
so. We shall observe that he finds it hardly less difficult to
compass a voluntary consciousness of what he has once learnt so
thoroughly that it has passed, so to speak, into the domain of
unconsciousness, than he found it to learn the note or passage in the
first instance. The effort after a second consciousness of detail
baffles him--compels him to turn to his music or play slowly. In
fact it seems as though he knew the piece too well to be able to know
that he knows it, and is only conscious of knowing those passages
which he does not know so thoroughly.