From The Annals of the Heechee by Frederik Pohl, in which the consciousness of Robinette Broadhead (who has been "vastened" to live after death as a machine-stored personality) is asking the simulation of Albert Einstein about his continuity of being:
You see 'me' in the sense that you see a waterfall. If you look at the Niagara Falls today, and come back a week later and look at it again, you will think you're seeing the same waterfall. In fact, not one atom of the waterfall is the same. The waterfall exists only because it is constrained to do so by the laws of hydraulics, and surface tension, and Newton's laws as they bear on the fact that one body of water is at a higher elevation than another. ... The water molecules are not Niagara Falls. They are only what Niagara Falls is made of.
The universe is the phenotype of physics.