Plato, Laws 846c

προσκλήσεων καὶ κλητήρων, εἴτʼ ἐπὶ δυοῖν εἴτʼ ἐφʼ ὁπόσων δεῖ καλεῖσθαι, καὶ πάντα ὁπόσα τοιαῦτά ἐστιν, οὔτʼ ἀνομοθέτητα οἷόν τʼ εἶναι γέροντός τε οὐκ ἄξια νομοθέτου, νομοθετούντων δʼ αὐτὰ οἱ νέοι πρὸς τὰ τῶν πρόσθεν νομοθετήματα ἀπομιμούμενοι, σμικρὰ πρὸς μεγάλα, καὶ τῆς ἀναγκαίας αὐτῶν χρείας ἐμπείρως ἴσχοντες, μέχριπερ ἂν πάντα ἱκανῶς δόξῃ κεῖσθαι· τότε δὲ ἀκίνητα ποιησάμενοι, ζώντων τούτοις ἤδη χρώμενοι μέτρον ἔχουσι.

and citations and evidence of citation,—whether the citation requires two or more witnesses,—and all matters of the like kind,—these cases cannot be left without legal regulation, but at the same time they do not deserve the attention of an aged lawgiver; so the young lawgivers shall make laws for these cases, modelling their small rules on the great ones of our earlier enactments, and learning by experience how far they are necessary in practice, until it be decided that they are all adequately laid down; and then, having permanently fixed them, they shall live in the practice of them, now that they are set out in due form.