Plato, Epinomis 981a

εἰ δʼ ἔχει τοῦτο οὕτως, τό γε πρῶτον ἡμῖν τοῦ πρώτου τῆς γενέσεως πιθανώτερον ἂν εἴη σχεδὸν ὑπηργμένον· καὶ θῶμεν δὴ τὴν ἀρχὴν τῆς ἀρχῆς εὐσχημονέστερον ἔχειν, καὶ τῶν μεγίστων σοφίας περὶ θεῶν γενέσεως ὀρθότατα ἐπιβαίνειν ἡμᾶς. ἔστω ταῦτα εἰς δύναμιν λεγόμενα. φέρε δή, ζῷόν γε ἀληθέστατα λέγεσθαι κατὰ φύσιν φῶμεν τοῦτό γε, ὅταν μία συνελθοῦσα σύστασις ψυχῆς καὶ σώματος ἀποτέκῃ μίαν μορφήν; ὀρθῶς.

what came first in that which first was born will more credibly seem almost to have been original. So let us take it that the beginning of the beginning is more august in state, and that we are most correctly entering upon wisdom in the greatest matters relating to the generation of the gods. Let this be so, as far as we can state it. Come then, shall we say that a living creature is most truly described by its nature, as a case of one combination of soul and body so uniting as to beget one shape? Correct.