tion of the law of association being,
as it were, sufficient to thrust the revived image into the centre of
the field of consciousness, as when the sight of a train recalls a
recent trip.

=B. Voluntary.=--At times the mind may set out with the deliberate aim,
or purpose, of reviving some forgotten experience. This is because
attention is at the time engaged upon a definite problem, as when the
student writing on his examination paper strives to recall the
conditions of the Constitutional Act. This type is known as voluntary
memory. Such a voluntary attempt at recall is, however, of the same
character as the involuntary type in that both involve association. What
the mind really strives for is to start a train of ideas which shall
suggest the illusive ideas involved in the desired answer. Such a
process of recall might be illustrated as follows:

[Illustration]

Here a, b, c, d, e represent the forgotten series of ideas to be
recalled. A, B, C, D, E represent other better known ideas, some of
which are associated with the desired ones. By having the mind course
over the better known facts--A, B, C, D, E, attention may finally focus
upon the relation A, a, B, and thus start up the necessary revival of a,
b, c, d, e.

=Attention May Hinder Memory.=--While active attention is thus able
under proper conditions to reinforce memory, yet occasionally attention
seems detrimental to memory. That such is the case will become evident
from the preceding figure. If the experience a, b, c, d, e, is directly
associated only with A, B, but the mind believes the association to
centre in C, D, E, attention is certain to keep focused upon the
sub-group--C, D, E. At an examination in history, for example, we may
desire to recall the circumstances associated with the topic, "The Grand
Remonstrance," and feel vaguely that this is connected with a
revolutionary movement. This may cause us, however, to fix attention,
not upon the civil war, but upon the revolution of 1688. In this case,
instead of forcing a nervous impulse into the proper centres, attention
is in reality diverting it into other channels. When, a few minutes
later, we have perhaps ceased our effort to remember, the impulse seems
of itself to stimulate the proper centres, and the necessary facts come
to us apparently without any attentive effort.

LOCALIZATION IN TIME

It has been pointed out that in an act of memory there must be a
recognition of the present experienc