Cicero, De Finibus
5.15.42 (tr. H. Rackham):
Infants just born lie helpless, as if absolutely inanimate; when they have acquired a little more strength, they exercise their mind and their senses; they strive to stand erect, they use their hands, they recognize their nurses; then they take pleasure in the society of other children, and enjoy meeting them, they take part in games and love to hear stories; they desire to bestow of their own abundance in bounty to others; they take an inquisitive interest in what goes on in their homes; they begin to reflect and to learn, and want to know the names of the people they see; in their contests with their companions they are elated by victory, discouraged and disheartened by defeat.
parvi enim primo ortu sic iacent, tamquam omnino sine animo sint; cum autem paulum firmitatis accessit, et animo utuntur et sensibus, conitunturque sese ut erigant, et manibus utuntur, et eos agnoscunt a quibus educantur; deinde aequalibus delectantur libenterque se cum iis congregant dantque se ad ludendum fabellarumque auditione ducuntur, deque eo quod ipsis superat aliis gratificari volunt, animadvertuntque ea quae domi fiunt curiosius, incipiuntque commentari aliquid et discere, et eorum quos vident volunt non ignorare nomina, quibusque rebus cum aequalibus decertant si vicerunt efferunt se laetitia, victi debilitantur animosque demittunt.