carried out by Charcot and his pupils, and also by such evidence as
was to be had at the time when he wrote on the curious memory
phenomena revealed by the use of hypnotism and by cases of spontaneous
dissociation. It is impossible to prove experimentally that no
experience is ever destroyed but it is becoming more and more firmly
established that enormous numbers of past experiences, which are
inaccessible to ordinary memory and which therefore it would seem
"natural" to suppose destroyed, can, if the right methods are
employed, be revived even with amazing fullness of detail.

In recent years since Bergson's books were first published, great
strides have been made in the experimental investigation of the whole
subject of memory, and the evidence thus obtained, far from upsetting
the theory of memory suggested to him by the less extensive evidence
which was available at the time when he wrote, lends it striking
support.

It appears to be accepted by doctors who use hypnotism in
psychotherapy that under hypnotism many patients can perfectly well be
taken back in memory to any period of their lives which the doctor
chooses to ask for, and can be made not only to remember vaguely a few
incidents which occurred at the time but actually to re-live the whole
period in the fullest possible detail, feeling over again with
hallucinatory vividness all the emotions experienced at the time.

This re-living of past experience can, with some patients, be made to
go on indefinitely, through the whole day, if the doctor has time to
attend to it, every little incident being faithfully recalled though
the actual event may have taken place 20 or 30 years previously. And
this happens not simply in the case of some very striking event or