Matt Ginsberg is an interesting guy. His Thursday, July 24 puzzle (answers) only gets the job half done leaving us the task of doubling up to make the clues work. It's a clever theme. Skip the next paragraph if you hate math, but be sure to read on after that.
The EULER formula is ei x = cos x + i sin x. If x is given the value π and you remember to do the trig in radians you get the elegant identity eπ i + 1 = 0. That one compact equation combines five of the most important numbers in math: e, π, i, 0, and 1, the fundamental operations addition, multiplication and exponentiation, the equality relation, and nothing else. It's a beautiful equation.
It's also the only clue I'm going to talk about so I can devote the rest of this post to an interview. Mr. Ginsberg and I started corresponding after I blogged about his previous puzzle and linked to this year-old bio. For background, you should know he's a well-known figure in the world of Artificial Intelligence.
MG: Sure, I'm happy to talk. The RG article got my background pretty well; one thing that they left out is that after my British fiancée dumped me, I needed something to do in the evenings instead of sitting around being miserable. Not only did I write a play, but I also built a stunt plane that I still own and fly around in. It's a real plane, cruising at 165 MPH. I also have very odd (but very deeply held) religious views.
JH: How did you get into constructing?
MG: In 1976. I wrote a program to fill crossword frames (the first one, I think). I revisited the problem from a technical perspective in 1990, writing an article about it that was accepted to the American Association of Artificial Intelligence's annual conference. Then I put it aside until 2006, when my company hired an idiot as president (I'm the CEO). The guy was everything an executive shouldn't be. We fired him around 11/06 but I was such a wreck from the whole process that I took a month off. Two weeks into that month, I got bored and figured I'd try construction. This was partly because a friend of mine named Pete Muller had been doing some and was having reasonable success with it.
JH: Are there particular puzzles or even clues that you're especially proud of?
MG: The puzzle I'm most proud of is called Takeaway Meal. It will come out as a second Sunday puzzle in the Times reasonably soon, I think. The puzzle I'm second most proud of is When in Rome ... It's unpublished because no one else likes it, though!
One of my favorite clues is [Fabled slacker] for HARE. Also [Unstated? (Abbr.)] for TERR. I like cluing, although I don't know if how I do it is legit. I use my clue database tool to get ideas, and then go from there to generate the best clue I can. But a reasonable fraction of my clues turn out to be similar to others that have been used before as a result. Unfortunately, when I do it the other way around (generate the clue, then check the database), they don't come out any fresher. I do work hard to try to make sure that very few of my clues are actual repeats.
JH: Will computers ever be able to construct puzzles as well as humans can?
MG: Computers will eventually be as good as we are at any given task. But it will be a while on crossword puzzles because so much world knowledge is needed -- especially on the construction side. (I'm a hopeless solver, by the way. Wednesdays are my limit.)
JH: How does the grid construction process work for you?
MG: I generally get a theme first. It's usually some sort of weird "idea"; it's very rare that I do puns because I'm no good at thinking them up. I've done a few quip puzzles, generally quips that I find amusing and the puzzle with very low word count. The theme idea pretty much just pops into my head somehow; I don't know how. Probably it is triggered by something I hear during the course of the day. Not an interesting phrase, usually, just an idea I can twist around.
Then I generate a long list of potential theme answers and use CCW to fill a frame. I don't think I'm terribly good at making the frames themselves although I'm getting better. My A.I. comes into it because the search that CCW is doing to fill the frames is a problem that I'm familiar with technically — I know what to do when CCW gets stuck, and can generally do a good job of filling a frame with a lot of theme content. I use a word list that I generated myself; about 3M entries statistically ranked by a wide range of properties (# of Google hits, previous uses, scrabble score, etc, etc).
I did rudely ask about his self-described "odd" religious views and he pointed me to this 62-page document. You might have heard the notion that mathematics is God. Mr. Ginsberg seems to go beyond that and hold that God is, in a very deep sense, Mathematics. Perhaps the Euler Identity can help provide the QED.