abnormal states
of mind is illustrated in the fact that in insanity the illusion of
taking past imaginations for past realities becomes far more powerful
and persistent. Abercrombie (_Intellectual Powers_, Part III. sec. iv. Sec.
2, "Insanity") speaks of "visions of the imagination which have formerly
been indulged in of that kind which we call waking dreams or
castle-building recurring to the mind in this condition, and now
believed to have a real existence." Thus, for example, one patient
believed in the reality of the good luck previously predicted by a
fortune-teller. Other writers on mental disease observe that it is a
common thing for the monomaniac to cherish the delusion that he has
actually gained the object of some previous ambition, or is undergoing
some previously dreaded calamity.

Nor is it necessary to these illusions of memory that there should be
any exceptional force of imagination. A fairly vivid representation to
ourselves of anything, whether real or fictitious, communicated by
others, will often result in something very like a personal
recollection. In the case of works of history and fiction, which adopt
the narrative tense, this tendency to a subsequent illusion of memory is
strengthened by the disposition of the mind at the moment of reading to
project itself backwards as in an act of recollection. This is a point
which will be further dealt with in the next chapter.

In most cases, however, illusions of memory growing out of previous
activities of the imagination appear only after the lapse of some time,
when in the natural course of things the mental images derived from
actual experience would sink to a certain degree of faintness. Habitual
novel-readers often catch themselves mistaking the echo of some passage
in a good story for the trace left by an actual event. A person's name,
a striking saying, and even an event itself, when we first come across
it or experience it, may for a moment seem familiar to us, and to recall
some past like impression, if it only happens to resemble something in
the works of a favourite novelist. And so, too, any recital of another's
experience, whether oral or literary, if it deeply interests us and
awakens a specially vivid imagination of the events described, may
easily become the starting-point of an illusory recollection.

Children are in the habit of "drinking in" with their vigorous and eager
imaginations what is told them and read to them, and hence the