Seneca, EM 125 7-9
“We say that being happy is what follows nature. And, moreover, what is according to nature is clear and obvious just as something that is complete is. That which is according to nature, what we touch at birth, I say is not the good but the beginning of the good.
You attribute the highest good–pleasure–to infants so that at the moment of birth a baby starts where the perfected adult should end. You place the branch in the root’s position! If anyone should claim that that child, hidden in the maternal womb, with unclear gender, tender, incomplete, and unshaped, that this child is already in some true good, then they would clearly seem to be lost in their ideas.
And yet how small is the difference between one who has just entered life and one who is still a hidden burden to their mother’s womb! They are equally knowing of the good and equally mature; An infant is no more conscious of the Good than a tree or any other speechless creature.”
Dicimus beata esse, quae secundum naturam sint, Quid autem secundum naturam sit, palam et protinus apparet, sicut quid sit integrum. Quod secundum naturam est, quod contigit protinus nato, non dico bonum, sed initium boni. Tu summum bonum, voluptatem, infantiae donas, ut inde incipiat nascens, quo consummatus homo pervenit.
Cacumen radicis loco ponis. Si quis diceret illum in materno utero latentem, sexus quoque incerti,tenerum et inperfectum et informem iam in aliquo bono esse, aperte videretur errare. Atqui quantulum interest inter eum, qui cum1 maxime vitam accipit, et illum, qui maternorum viscerum latens onus est? Uterque, quantum ad intellectum boni ac mali, aeque maturus est, et non magis infans adhuc boni capax est quam arbor aut mutum aliquod animal.