of the sound uttered by the nightingale. Since the sounds uttered by all living beings
are produced by the same kind of mental process referred to above, the Yogi can al-
ways come to know their meaning through Samyama.
It is not necessary for the Yogi to sit down in meditation to know the meaning
of such sounds. Once the technique of Samyama is mastered and he has learnt to re-
solve the complex process which results in the external sounds he can go through the
process almost instantaneously and thus know the meaning on hearing the sounds.
- By direct perceptions of the impressions a knowledge of the previous
birth.
It is a part of the doctrine of reincarnation that all the experiences which we
pass through in life produce impressions upon our vehicles and can thus be recovered
from them by the application of proper methods. Experiments in hypnotism have
shown conclusively that experiences which a person has passed through in physical
life are indelibly impressed upon his brain even though he may not be able to remem-
ber them. This is proved by the fact that they can be recovered by putting him under
hypnosis. In fact, by pushing hypnosis to deeper levels even impressions of previous
lives can be revived. For example, a person who did not know even the rudiments of a
language was found under hypnosis to talk fluently in that language and to show the
characteristics of an entirely new personality. This shows that impressions connected
with all the lives we have passed through are present somewhere within us and by div-
ing sufficiently deep into our own consciousness it should be possible to revive the
experiences which have produced those impressions, just as by playing a gramophone
record it is possible to recover the sounds which produced the impressions on the re-
cord.
These impressions of previous lives can be present only in some vehicle which
has passed through all those lives and has not been newly formed with each incarna-
tion like the physical body. This vehicle is called Karana Sarira or causal body and is