Man and wife

Even if all you care about is what happens in the next ten feet, this is the right answer. I think we can and should do the same thing with programming languages. Notes I believe Lisp Machine Lisp was the first language to embody the principle that declarations (except those of dynamic variables) were merely optimization advice, and would not change the meaning of a correct program. Common Lisp seems to have been the first to state this explicitly. Thanks to Trevor Blackwell, Robert Morris, and Dan Giffin for reading drafts of this, and to Guido van Rossum, Jeremy Hylton, and the rest of the Python crew for inviting me to speak at PyCon. If Lisp is So Great If Lisp is so great, why don't more people use it? I was asked this question by a student in the audience at a talk I gave recently. Not for the first time, either. In languages, as in so many things, there's not much correlation between popularity and quality. Why does John Grisham (King of Torts sales rank, 44) outsell Jane Austen (Pride and Prejudice sales rank, 6191)? Would even Grisham claim that it's because he's a better writer? Here's the first sentence of Pride and Prejudice: It is a truth universally acknowledged, that a single man in possession of a good fortune must be in want of a wife. "It is a truth universally acknowledged?" Long words for the first sentence of a love story ...»