we're not even the same, surface-level anyway, from moment to moment. Like waves on the ocean, we're floating, up and down -- down and up. Portions of us, like the water columns exchanging content up and down, switch over the day.

To extend that analogy, I'd also like to think that the deeper we go, the less ever-changing we are. The deep ocean, the bedrock at the bottom of the water, is pretty firm and pretty solid -- like our characters and core beings.

Or something like that