Heraclitus

No man ever steps in the same river twice, for it's not the same river and he's not the same man.  

(You cannot step into the same river twice).

All is flux, nothing stays still.
Nothing endures but change.
A man's character is his fate.

λέγει που Ἡράκλειτος, ὅτι πάντα χωρεῖ, καὶ οὐδὲν μένει· καὶ ποταμοῦ ῥοῇ ἀπεικάζων τὰ ὄντα λέγει, ὡς δὶς ἐς τὸν αὐτὸν ποταμὸν οὐκ ἂν ἐμβαίης. 

(πάντα χωρεί και ουδέν μένει και ποταμού ροή απεικάζων τα όντα λέγει ως δις εις τον αυτόν ποταμόν ουκανεμβαίης)

Ta panta rhei!