Tertullian

“ And here, therefore, we draw our conclusion, that all the natural properties of the soul are inherent in it as parts of its substance; and that they grow and develope along with it, from the very moment of its own origin at birth. Just as Seneca says, whom we so often find on our side: [1] “There are implanted within us the seeds of all the arts and periods of life. And God, our Master, secretly produces our mental dispositions;” that is, from the germs which are implanted and hidden in us by means of infancy, and these are the intellect: for from these our natural dispositions are evolved. ”

“ Stoutness hinders knowledge, but a spare form stimulates it; paralysis prostrates the mind, a decline preserves it. How much more will those accidental circumstances have to be noticed, which, in addition to the state of one’s body or one’s health, tend to sharpen or to dull the intellect! ”

“ It is evident how great must be the influences which so variously affect the one nature of the soul, since they are commonly regarded as separate “natures.” Still they are not different species, but casual incidents of one nature and substance—even of that which God conferred on Adam, and made the mould of all (subsequent ones) . Casual incidents will they always remain, but never will they become specific differences. However great, too, at present is the variety of men’s maunders, it was not so in Adam, the founder of their race. ”