Uncountably many will that differ from you by random degree on uncountably many dimensions. How much like you do they have to be, to actually be you? Everybody

Uncountably many will that differ from you by random degree on uncountably many dimensions. How much like you do they have to be, to actually be you? Everybody reading this differs from you by only small degree. You differ from yourself-of-yesterday by a typically smaller amount, and -of-last-year by a less-small amount.