Remember That I Too Am Mortal.

Morals Are A Luxury Of The Rich.

It Is Feeling That Sets A Man Thinking, And Not Thought That Sets Him Feeling.

I Have To Live For Others And Not For Myself: That's Middle-class Morality.

I Was A Freethinker Before I Knew How To Think.

Science Is Always Simple And Always Profound. It Is Only The Half-truths That Are Dangerous.