"Death, so called, is but older matter dressed
In some new form. And in a varied vest,
From tenement to tenement though tossed,
The soul is still the same, the figure only lost."

_Poem on Pythagoras, Dryden's Ovid._

Here it may be asked, if we existed before our birth why do we not
remember? This is one of the strongest objections often raised against
the belief in pre-existence. Some people deny the existence of the
soul in the past simply because they cannot remember the events of
their past. Others, again, who hold memory as the standard of
existence, say, if our memory of the present ceases to exist at the
time of death, with it we shall also cease to be; we cannot be
immortal; because they hold that memory is the standard of life, and
if we do not remember then we are not the same beings.

Vedanta answers these questions by saying that it is possible for us
to remember our previous existences. Those who have read "Raja Yoga"
will recall that in the 18th aphorism of the third chapter it is said:
"By perceiving the Samskaras one acquires the knowledge of past
lives." Here the Samskaras mean the impressions of the past experience
which lie dormant in our subliminal self, and are never lost. Memory
is nothing but the awakening and rising of latent impressions above
the threshold of consciousness. A Raja Yogi, through powerful
concentration upon these dormant impressions of the subconscious mind,
can remember all the events of his past lives. There have been many
instances in India of Yogis who could know not only their own past
lives but correctly tell those of others. It is said that Buddha
remembered five hundred of his previous births.