Plato, Laws 815b

καὶ ψυχῶν ὁπόταν γίγνηται μίμημα, εὐθυφερὲς ὡς τὸ πολὺ τῶν τοῦ σώματος μελῶν γιγνόμενον, ὀρθὸν μὲν τὸ τοιοῦτον, τὸ δὲ τούτοις τοὐναντίον οὐκ ὀρθὸν ἀποδεχόμενον. τὴν δὲ εἰρηνικὴν ὄρχησιν τῇδʼ αὖ θεωρητέον ἑκάστων, εἴτε ὀρθῶς εἴτε μὴ κατὰ φύσιν τις τῆς καλῆς ὀρχήσεως ἀντιλαμβανόμενος ἐν χορείαις πρεπόντως εὐνόμων ἀνδρῶν διατελεῖ. τὴν τοίνυν ἀμφισβητουμένην ὄρχησιν δεῖ πρῶτον χωρὶς τῆς

in which most of the limbs of the body are extended straight: this kind of representation is right, but the opposite kind we pronounce to be wrong. In pacific dancing, the point we must consider in every case is whether the performer in his dances keeps always rightly, or improperly, to the noble kind of dancing, in the way that befits law-abiding men. So, in the first place, we must draw a line between questionable dancing and dancing that is above question.