Baldassare Castiglione

Then the soul, freed from vice, purged by studies of true philosophy, versed in spiritual life, and practised in matters of the intellect, devoted to the contemplation of her own substance, as if awakened from deepest sleep, opens those eyes which all possess but few use, and sees in herself a ray of that light which is the true image of the angelic beauty communicated to her, and of which she then communicates a faint shadow to the body.

I have discovered a universal rule which seems to apply more than any other in all human actions or words: namely, to steer away from affectation at all costs, as if it were a rough and dangerous reef, and (to use perhaps a novel word for it) to practise in all things a certain nonchalance [sprezzatura] which conceals all artistry and makes whatever one says or does seem uncontrived and effortless.