Charles Darwin — "The expression of the emotions in man and animals."

"The fact that I can't remember anything from the first three years of my life is no proof that I wasn't an embryo then."

"The love of experiment and the patient observation of nature are the two great qualifications for a naturalist."

"As a proof of the admirable power of the mind, I may mention that I have been for some years training my mind to reject the evidence of my senses when they do not square with my preconceived notions."

"If I had my life to live over again, I would have made a rule to read some poetry and listen to some music at least once every week."

"It is a cursed evil to any man to become so absorbed in any one subject as I am in mine."