Donald Knuth Quotes

I came to philosophy finally phrased as "0.8 is enough". … If I had a way to rate happiness, I think it's a good design to have an organism that's happy about 80% of the time. If it was 100% of the time, it would be like everybody's on drugs and everything collapses and nothing works because everybody is just too happy. … There are times when I am down and I know that I've actually been programmed to be depressed a certain amount of time.

I am assuming that God exists and I am glad that there is no way to prove this. [Because] I would run through the proof once, and then I'd forget it, and I would never speculate about spiritual things and mysteries otherwise. And, I think, my life would be very incomplete.

A good technical writer, trying not to be obvious about it, but says everything twice: formally and informally. Or maybe three times.

In a way, you'd say my life is a convex combination of English and mathematics. ... And not only that, I want my kids to be that way: use left brain, right brain at the same time – you got a lot more done. That was part of the bargain.

If you find that you're spending almost all your time on theory, start turning some attention to practical things; it will improve your theories. If you find that you're spending almost all your time on practice, start turning some attention to theoretical things; it will improve your practice.

In fact, my main conclusion after spending ten years of my life working on the T_EX project is that software is hard. It’s harder than anything else I’ve ever had to do.

How can you own [...] numbers? Numbers belong to the world.

Email is a wonderful thing for people whose role in life is to be on top of things. But not for me; my role is to be on the bottom of things. What I do takes long hours of studying and uninterruptible concentration.

I can’t go to a restaurant and order food because I keep looking at the fonts on the menu.

I define UNIX as 30 definitions of regular expressions living under one roof.

A mathematical formula should never be "owned" by anybody! Mathematics belong to God.

Science is what we understand well enough to explain to a computer. Art is everything else we do.

The whole thing that makes a mathematician’s life worthwhile is that he gets the grudging admiration of three or four colleagues.

The important thing, once you have enough to eat and a nice house, is what you can do for others, what you can contribute to the enterprise as a whole.

The psychological profiling [of a programmer] is mostly the ability to shift levels of abstraction, from low level to high level. To see something in the small and to see something in the large.