Since the wings are swifter to press the air than the air is to escape from beneath the wings the air becomes condensed and resists the movement of t… - Leonardo da Vinci

Though I may not, like them, be able to quote other authors, I shall rely on that which is much greater and more worthy – on experience, the mistress of their Masters

The eye which turns from a white object in the light of the sun and goes into a less fully lighted place will see everything as dark.

They will say that I, having no literary skill, cannot properly express that which I desire to treat of, but they do not know that my subjects are to be dealt with by experience rather than by words. And [experience] has been the mistress of those who wrote well. And so, as mistress, I will cite her in all cases. Though I may not, like them, be able to quote other authors, I shall rely on that which is much greater and more worthy: on experience, the mistress of their masters.