Earlier this week Don Knuth turned 70. This posting, inspired by a coordinated series of posts by admirers in mathematics and computer scientists, is my own personal statement of appreciation of his work. Mostly, I’ve been influenced by TeX, which Don Knuth wrote both as a labour of love, and as a means to the end of writing his multi-volume work The Art of Computer Programming (which is also a labour of love).

My first real contact with TeX was in 1987, five years after the first release of what has become the current version of TeX. Now the version number of TeX is, famously, converging to pi, but then it was something like 2.1. Previously I had written my PhD thesis out by hand, and skilled technical typists typed it up page by page, using the admirable IBM golfball typewriters. To obtain a special symbol, the typists had to manually change the golf-ball sized typehead. In 1986/7 I wrote a mathematics paper user the eqn preprocessor and the troff typesetting system that came with Unix. I was able to do this only because I had a lot of help from a technical typist who had several years experience with troff.