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

“Less than fifteen percent of the people do any original thinking on any subject . . . The greatest torture in the world for most people is to think”

“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 hours of folly are measured by the clock, but of wisdom no clock can measure.”

“The investigation of the meaning of words is the beginning of education”

“One must be a wise reader to quote wisely and well”