“I am not the least afraid to die.”
“I love fools experiments. I am always making them.”
“A man's friendships are one of the best measures of his worth.”
“A man who dares to waste one hour of his life has not discovered the value of life.”
“It is a cursed evil to any man to become as absorbed in any subject as I am in mine.”
“The highest possible stage in moral culture is when we recognize that we ought to control our thoughts.”
“It is not the strongest of the species that survive, nor the most intelligent, but the one most responsive to change.”
“What a book a devil's chaplain might write on the clumsy, wasteful, blundering, low, and horribly cruel work of nature!”