“There’s no persisting and unitary self.”
One of the characteristic arguments of Nietzsche is for the non-unitary nature of the self. While I think there is some basis for this argument, I believe it is in fact possible to find a satisfying approach to understanding what personal identity actually might be:
Also it seems to me that the experience of pain demonstrates that there is a unitary self. There is no escaping pain. It compels our full attention. It can rarely be put out of mind. It is not possible to banish severe pain to the unconscious or to ignore it. Pain is a reminder that we are singular and solitary beings that suffer personally in a unitary manner.
I would also maintain that this solitary personal suffering has its substrate in an individual soul or spirit:
In terms of a persistent self, I feel we would agree that – although we will not be exactly the person we are now in a year’s time – we would be apprehensive of a painful experience that would occur then.
A pregnant woman cannot avoid fearing the pain of childbirth by telling herself that in nine months time she will be a different woman.