“Learning is the only thing the mind never exhausts, never fears, and never regrets.”

“Learning never exhausts the mind.”

“Art is never finished, only abandoned.”

“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.”

“A wave is never found alone, but is mingled with the other waves.”

“I thought I was learning to live; I was only learning to die.”

“He who loves practice without theory is like the sailor who boards ship without a rudder and compass and never knows where he may cast.”