Posts published in October 2011

John McCarthy, creator of Lisp and one of the founders of the field of artificial intelligence, has died. He changed the world more than Steve Jobs ... but in a far subtler way, by laying the foundation for programs like Apple's Siri through his artificial intelligence work, or more broadly by laying the foundation for much of modern computing through innovations like the IF-THEN-ELSE formalism. It's important not to overstate the impact of great men like John and Steve; artificial intelligence pioneers like Marvin Minsky would have pushed us forward without John, and companies like Xerox and Microsoft would have pushed us forward without Steve. But we're certainly better off, and farther along, with their contributions. I have only three stories to tell about John McCarthy. The third story is that I last saw him at a conference at IBM, in a mobile scooter and not looking very well. Traveling backwards in time, the second story is that I spoke with one of his former graduate students, who saw a John McCarthy poster in my office, and told me John's illness had progressed to the point where he basically couldn't program any more and that he was feeling very sad about it. But what I want to remember is my first encounter with John ... it's been a decade and a half, so my memory's fuzzy, but I recall it was at AAAI-97 in Providence, Rhode Island. I'd arrived at the conference in a terrible snafu and had woken up a friend at 4 in the morning because I had no place to stay. I wandered the city looking for H.P. Lovecraft landmarks and had trouble finding them, though I did see a house some think inspired Dreams in the Witch House. But near the end, at a dinner for AI folks, I want to say at Waterplace Park but I could be misremembering, I bumped in to John McCarthy. He was holding court at the end of the table, and as the evening progressed I ended up following him and a few friends to a bar, where we hung out for an evening. And there, the grand old man of artificial intelligence, still at the height of his powers, regaled the wet-behind-the-ears graduate student from Atlanta with tales of his grand speculative ideas, beyond that of any science fiction writer, to accelerate galaxies to the speed of light to save shining stars from the heat death of the universe. We'll miss you, John. -Anthony Image stolen shamelessly from Zach Beane's blog. The title of this post is taken from the Lisp 1.5 Programmer's Manual, and is the original, pre-implementation Lisp M-expression notation for code to remove an item from a list.