When I was 4 years old ... I dreamt that I'd been eaten by a wolf, and to my great surprise I was in the wolf's stomach and not in heaven. - Bertrand Russell

Organic life, we are told, has developed gradually from the protozoon to the philosopher, and this development, we are assured, is indubitably an advance. Unfortunately it is the philosopher, not the protozoon, who gives us this assurance.

I do not pretend to start with precise questions. I do not think you can start with anything precise. You have to achieve such precision as you can, as you go along.

Men fear thought as they fear nothing else on earth — more than ruin, more even than death. Thought is subversive and revolutionary, destructive and terrible, thought is merciless to privilege, established institutions, and comfortable habits; thought is anarchic and lawless, indifferent to authority, careless of the well-tried wisdom of the ages. Thought looks into the pit of hell and is not afraid ... Thought is great and swift and free, the light of the world, and the chief glory of man.