But by far the greatest obstacle to the progress of science and to the undertaking of new tasks and provinces therein is found in this-that men despair and think things impossible.
I use all sorts of things to work with: old brooms, old sweaters, and all kinds of peculiar tools and materials... I paint to excite myself, and make something for myself.
In revenge a man is but even with his enemy; for it is a princely thing to pardon, and Solomon saith it is the glory of a man to pass over a transgression.
Libraries are as the shrine where all the relics of the ancient saints, full of true virtue, and that without delusion or imposture, are preserved and reposed.
For many parts of Nature can neither be invented with sufficient subtlety, nor demonstrated with sufficient perspicuity, nor accommodated unto use with sufficient dexterity, without the aid and intervening of the mathematics, of which sort are perspective, music, astronomy, cosmography, architecture, engineery, and divers others.
I have to hope that my instincts will do the right thing, because I can't erase what I have done. And if I drew something first, then my paintings would be illustrations of drawings.
Begin doing what you want to do now. We are not living in eternity. We have only this moment, sparkling like a star in our hand - and melting like a snowflake.
Again there is another great and powerful cause why the sciences have made but little progress; which is this. It is not possible to run a course aright when the goal itself has not been rightly placed.