“For the end containing the time of each animal, beyond which there is no time in accordance with nature, has been called the age of each them.”

ὸ γὰρ τέλος τὸ περιέχον τὸν τῆς ἑκάστου ζωῆς χρόνον, οὗ μηθὲν ἔξω κατὰ φύσιν, αἰὼν ἑκάστου κέκληται.

Aristotle, De caelo 1.9, 279a23-30

“At seven years, a child, when he is still young and immature, loses the first set of teeth he has grown. When the god grants him another seven years, the child shows signs of coming puberty. At the third, as the body grows, the chin grows a beard, while the blush of the skin begins to change. At the fourth seven-year period, everyone is at their best in strength, and by it men make a trial of the excellence they have. At the fifth, it is time for a man to be reminded of marriage and to seek for a generation of children to come after him. At the sixth, a man’s mind is training in all things, and likewise he no longer wishes to do foolish things. At the seventh seven-year period, he is best in mind and speech, and at the eighth as well—in all, fourteen years. At the ninth, he is still powerful, but his speech and wisdom are softer in extent of excellence than they were. But if someone, having completed the measure, gets to the tenth (i.e., 70 years), he would not receive the fate of death at the wrong season.”

παῖς μὲν ἄνηβος ἐὼν ἔτι νήπιος ἕρκος ὀδόντων φύσας ἐκβάλλει πρῶτον ἐν ἕπτ' ἔτεσιν. τοὺς δ' ἑτέρους ὅτε δὴ τελέσηι θεὸς ἕπτ' ἐνιαυτούς, ἥβης †δὲ φάνει† σήματα γεινομένης. τῆι τριτάτηι δὲ γένειον ἀεξομένων ἔτι γυίων λαχνοῦται, χροιῆς ἄνθος ἀμειβομένης. τῆι δὲ τετάρτηι πᾶς τις ἐν ἑβδομάδι μέγ' ἄριστος ἰσχύν, ἧι τ' ἄνδρες πείρατ' ἔχουσ' ἀρετῆς. πέμπτηι δ' ὥριον ἄνδρα γάμου μεμνημένον εἶναι καὶ παίδων ζητεῖν εἰσοπίσω γενεήν. τῆι δ' ἕκτηι περὶ πάντα καταρτύεται νόος ἀνδρός, οὐδ' ἔρδειν ἔθ' ὁμῶς ἔργ' ἀπάλαμνα θέλει. ἑπτὰ δὲ νοῦν καὶ γλῶσσαν ἐν ἑβδομάσιν μέγ' ἄριστος ὀκτώ τ'· ἀμφοτέρων τέσσαρα καὶ δέκ' ἔτη. τῆι δ' ἐνάτηι ἔτι μὲν δύναται, μαλακώτερα δ' αὐτοῦ πρὸς μεγάλην ἀρετὴν γλῶσσά τε καὶ σοφίη. τὴν δεκάτην δ' εἴ τις τελέσας κατὰ μέτρον ἵκοιτο, οὐκ ἂν ἄωρος ἐὼν μοῖραν ἔχοι θανάτου.

Solon, fragment 27 West