§7.47.1Περισκοπεῖν ἄστρων δρόμους ὥσπερ συμπεριθέοντα καὶ τὰς τῶν στοιχείων εἰς ἄλληλα μεταβολὰς συνεχῶς ἐννοεῖν· ἀποκαθαίρουσι γὰρ αἱ τούτων φαντασίαι τὸν ῥύπον τοῦ χαμαὶ βίου.
To observe the courses of the stars as if running along with them, and constantly to ponder the changes of the elements into one another; for the representations of these things wash away the filth of the earth-bound life.