Each person bears a fear which is special to him. One man fears a close space and another man fears drowning; each laughs at the other and calls him stupid. Thus fear is only a preference, to be counted the same as the preference for one woman or another, or mutton for pig, or cabbage for onion.

Keep working. Don't wait for inspiration. Work inspires inspiration. Keep working.

Historically, the claim of consensus has been the first refuge of scoundrels; it is a way to avoid debate by claiming that the matter is already settled.

Exercise invigorates the body and sharpens the mind.

The greatest challenge facing mankind is the challenge of distinguishing reality from fantasy, truth from propaganda.

This is the gift of your species and this is the danger, because you do not choose to control your imaginings. You imagine wonderful things and you imagine terrible things, and you take no responsibility for the choice. You say you have inside you both the power of good and the power of evil, the angel and the devil, but in truth you have just one thing inside you - the ability to imagine.

At forty, I was too old to work as a programmer myself anymore; writing code is a young person’s job.