Transmigration

‘Transmigration’ (known In Ancient Greek as metempsuchosis) is the concept of the soul’s leaving the body at death, or entering it at birth.

Reincarnation

The journey of the soul to and from the body.

If the soul is not made of matter, as the body is, then the soul should not be destroyed by the death of the body. Similarly, if the soul is a non-material entity there is no reason not to think it existed prior to the body.