ποταμῷ γὰρ οὐκ ἔστιν ἐμβῆναι δὶς τῷ αὐτῷ → it is impossible to step twice in the same river, you cannot step twice into the same rivers
τοκοντό κλαδί.[ΕΤΥΜΟΛ. < κοντ(ο)- + κλαδί.