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.
Leonardo da Vinci