What it Means to Live in a Land Gone Politically Correct It's a PC World:

Now, the program that I did yesterdayБЂ”I have no idea how I would state all of the assertions that are there. I would never get done because I wouldnБЂ™t have any more confidence in my assertions than I would in the program. Or TeX, for example, is a formal mess. It was intended to be for human use, not for computer use. To define what it means for TeX to be correct would be incomprehensible. Some methods for formal semantics are so complicated that nobody can comprehend the definition of correctness. Seibel: When you were working on TeX you wrote a really horrendous torture test of the program. Knuth: Right. Seibel: How do you get in the frame of mind to do that? Programmers often tend to want to protect their baby, and so they donБЂ™t test as hard as they could. Knuth: Well, IБЂ™ve been a nitpicker all my life. So if I can get my kicks out of finding errors then I just have to make sure that I forget that I was the author of the program. I try to imagine that somebody else was the author. But otherwise itБЂ™s fairly easy for me to get into attack mode. I donБЂ™t know why ...»