“It is well for people who think to change their minds occasionally in order to keep them clean. For those who do not think, it is best to at least rearrange their prejudices once in a while”

“The customs and fashions of men change like leaves on the bough, some of which go and others come”

“Give me a lever long enough, and a prop strong enough, I can single-handed move the world”

“This life is a hospital in which every patient is possessed with a desire to change his bed”

“The man who never alters his opinions is like standing water, and breeds reptiles of the mind”

“There are no shortcuts in evolution”