I’m talking about an old friend. Someone you haven’t seen in years: two, three, five years. You meet and it’s just like old times. You’re right back where you were the last time you’d been together. As though no time had passed.
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What’s that say about friendship, but also about minds, brains, and time?
If we didn’t have a calendar to measure the time between, would the easy familiarity seem less remarkable? But still, we do measure time by daily sun-cycles, monthly moon cycles, and yearly sun-cycles.
If a friendship is a succession of brain states – one in each party to the friendship – then the meeting is simply one more in the succession. It joins the last state in the succession and so the friendship continues on.