Nature never breaks her laws.

The painter's work will be of little merit if he takes the painting of others as his standard, but if he studies from nature he will produce good fruits.

O time! swift devourer of all created things!

The imagination is to the effect as the shadow to the opaque body which causes the shadow.

He is a poor disciple who does not surpass his master.

They who are enamoured of practice without knowledge are like the mariner who puts to sea in a vessel without rudder or compass, and who navigates without a course.

Faults are more easily recognized in the works of others than in our own.

The good painter has two principal things to depict: man and the purpose of his mand. The first is easy, the second is difficult, since he must do it by the gestures and movements of the limbs, and this is to be learnt from the dumb, who more than all other men excel in it.

Fame should be depicted covered with tongues instead of with feathers and in the form of a bird.

There is no human experience that can be termed true science unless it can be mathematically demonstrated. And if thou sayest that the sciences which begin and end in the mind are true, this cannot be conceded, but must be denied for many reasons, and firstly because in such mental discourses experience is eliminated, and without experience there can be no certainty.