Science is what we know, and philosophy is what we don't know. - Bertrand Russell

It is not altogether true that persuasion is one thing and force is another. Many forms of persuasion – even many of which everybody approves – are really a kind of force. Consider what we do to our children. We do not say to them: "Some people think the earth is round, and others think it is flat; when you grow up, you can, if you like, examine the evidence and form your own conclusion." Instead of this we say: "The earth is round." By the time our children are old enough to examine the evidence, our propaganda has closed their minds.

Every isolated passion, is, in isolation, insane; sanity may be defined as synthesis of insanities. Every dominant passion generates a dominant fear, the fear of its non-fulfillment. Every dominant fear generates a nightmare, sometimes in form of explicit and conscious fanaticism, sometimes in paralyzing timidity, sometimes in an unconscious or subconscious terror which finds expression only in dreams. The man who wishes to preserve sanity in a dangerous world should summon in his own mind a parliament of fears, in which each in turn is voted absurd by all the others.

The greatest challenge to any thinker is stating the problem in a way that will allow a solution.