Evidence of the soul

Introspection is the evidence for the existence of the soul. You have experience. That proves that the soul exists. But, I think you are asking, What is the evidence a) that your soul is immortal? or b) that your soul survives the death of the body? or c) that your soul is separable from the body? These are more difficult questions to provide evidence for.

When my grandmother was in a care home and suffering from dementia, she would occasionally mention things that had recently taken place at the house she previously shared with my mother. Somehow my grandmother knew that furniture had been rearranged--and in what manner. She knew that my mother now had a dog--even though no one told her. It was as if her soul would occasionally leave her body during these moments of dementia journey back to her old home and look around. Perhaps death is not a magical change that involves the life of the soul. Perhaps, as Shamans will attest,the soul can take journeys while the body is alive. Perhaps when the brain is comatose or dead, it is like turning off the TV. The soul that was so focused on the program of the life of the body now isn't distracted by the body's program and can have broader experiences.

First, introspection is a kind of evidence. It lacks intersubjectivity, but that does not invalidate it. As for the whether the soul is immortal or can survive the existence of the body or can live without the body, I think there is evidence that speaks to those issues as well. Reports of Near Death Experiences are one form of evidence, though we must be careful no to learn more from them than they can teach. Religious and mystical experiences are also a type of evidence. There clearly are beliefs about these issues as well. A belief may or may not have a relation to empirical evidence.