The representation of the sizes that objects placed before the eye naturally have: the nearest figures, being small, must be rendered as finished as are the works of the miniaturists, just as the large ones are for painters; but the small works of the miniaturists must be seen from close by, and those of the painter from far off, for by doing so these figures come to the eye at an equal size, and this arises because they come with an equal breadth of angle. It is proved thus: let the object be b c, the eye be a, and let d e be a plate of glass through which the images of b c pass. I say that, the eye a remaining fixed, the size of the painting made in imitation of that b c must be a figure smaller in proportion as the glass d e is nearer to the eye a, and it must be equally finished. And if you finish that figure b c on the glass d e, your figure must be less finished than the figure b c, and more finished than the figure n m made on the glass f g; because if the figure p o were finished as much as the natural b c, the perspective of that o p would be false, for as regards the diminution of the figure it would be right, b c being diminished into p o, but the degree of finish would not agree with the distance; because in seeking the perfection of finish of the natural b c, then that b c would seem to lie at the nearness o p; but if you wish to seek the diminution of o p, that o p seems to lie at the distance b c, and in the lessening of the finish upon the glass f g.