All our knowledge hast its origins in our perceptions … In nature there is no effect without a cause … Experience never errs; it is only your judgments that err by promising themselves effects such as are not caused by your experiments … Science is the observation of things possible, whether present or past; prescience is the knowledge of things which may come to pass.
Leonardo da VinciTest knowledge through experience, be prepared to make mistakes, and be persistent about it.
Leonardo da VinciWho would believe that so small a space could contain the images of all the universe?
Leonardo da Vinci