Recently I came across an interview of him here.
A few thoughts after reading the interview script:
- I admire Knuth's passion on CS: He loves what he is doing. Even at his age (70), he is still writing and studying computer science. Compare this with some university grads who throw books away once they graduate and got their diplomas.
- Knuth is keeping relatively abreast with technology. For example, he talks about the recent development in multicore CPUs, and he does his work on a PC running Ubuntu, and for backup purpose he uses backupfs, which is still in beta stage. I am amazed he dares to leave his comfort zones to try new stuff. I need to confess I am no longer that willing to leave my own comfort zones, and Knuth does give me a positive example to ponder upon and learn from.
- Humility: Knowing when to say "I don't know" needs a non-trivial amount of life experience, wisdom, and confidence. For example when talking about programming parallel machines, he readily admitted there are people who know better than he does.
"[snip]... the half-life of parallel techniques is very short, because hardware changes rapidly and each new machine needs a somewhat different approach. So I decided long ago to stick to what I know best. Other people understand parallel machines much better than I do; programmers should listen to them, not me, for guidance on how to deal with simultaneity."