My work was fairly theoretical. It was in recursive function theory. And in particular, hierarchies of functions in terms of computational complexity. I got involved in real computers and programming mainly by being - well, I was interested even as I came to graduate school.

At MIT, mostly what I did was documentation. I sort of read things. Wrote some descriptions of various aspects of the file system. Did not really do very much programming at all. At least on Multics.

One of the obvious things that went wrong with Multics as a commercial success was just that it was sort of over-engineered in a sense. There was just too much in it.

Dennis Ritchie Quotes