Let proportion be found not only in numbers and measures, but also in sounds, weights, times, and positions, and what ever force there is.

The color of the object illuminated partakes of the color of that which illuminates it.

Good culture is born of a good disposition; and since the cause is more to be praised than the effect, I will rather praise a good disposition without culture, than good culture without the disposition.

Perspective is nothing more than a rational demonstration applied to the consideration of how objects in front of the eye transmit their image to it, by means of a pyramid of lines. The Pyramid is the name I apply to the lines which, starting from the surface and edges of each object, converge from a distance and meet in a single point.

People reveal themselves completely only when they are thrown out of the customary conditions of their life.

Beyond a doubt truth bears the same relation to falsehood as light to darkness.

The young man should first learn perspective, then the proportions of objects. Next, copy work after the hand of a good master, to gain the habit of drawing parts of the body well; and then to work from nature, to confirm the lessons learned.