Leonardo DaVinci

The tears come from the heart and not from the brain.

declaimers of the works of others, must be regarded and not otherwise esteemed than as the object in front of a mirror, when compared with its image seen in the mirror. For the first is something in itself, and the other nothingness – folks little indebted to Nature, since it is only by chance that they wear the human form and without it I might class them with the herds of beasts.

The sorest misfortune is when your views are in advance of your work

And if you call painting dumb poetry, the painter may call poetry blind painting. Now which is the worse defect? To be blind or dumb?

The first thing in painting is that the objects it represents should appear in relief, and that the grounds surrounding them at different distances shall appear within the vertical plane of the foreground of the picture by means of the 3 branches of Perspective, which are: the diminution in the distinctness of the forms of the objects; the diminution in their magnitude; and the diminution in their colour.

Experiment [showing] the dilatation and contraction of the pupil, from the motion of the sun and other luminaries. In proportion as the sky is darker the stars appear of larger size, and if you were to light up the medium these stars would look smaller; and this difference arises solely from the pupil which dilates and contracts with the amount of light in the medium which is interposed between the eye and the luminous body.

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Of several bodies, all equally large and equally distant, that which is most brightly illuminated will appear to the eye nearest and largest.

You know that in an atmosphere of equal density the remotest objects seen through it, as mountains, in consequence of the great quantity of atmosphere between your eye and them – appear blue and almost of the same hue as the atmosphere itself when the sun is in the East

space between the extreme poles inside and outside the foot called the ankle or ankle bone a b is equal to the space between the mouth and the inner corner of the eye.

The foot, from where it is attached to the leg, to the tip of the great toe is as long as the space between the upper part of the chin and the roots of the hair a b; and equal to five sixths of the face.