The Ecphorizer

Psyching out a chess-playing computer

"...It is like a dog walking on its hind legs. It is not done well; but you are surprised to find it done at all." Samuel Johnson

Over the years I have heard fellow chess players discussing

...its moves generally make sense; I've played worse real ones.

[quoteright]Last Christmas I got my chance. My wife bought me a Fidelity Sensory Chess Challenger (the dumb one, not the talking one, thank God). Fidelity Electronics products are the most frequently-seen and probably the most reasonably-priced of these contraptions.

The sensory models are the ones with the touch-sensitive board. While older machines required that the player key in his moves on a keyboard, these respond to gentle pressure; little lights wink at you to signal that you are doing the right thing.

Certain ways the machine has of responding, like darkening its lights briefly in a wince of electronic pain before making moves in bad positions, or refusing to move at all in very tight positions, remind me of the behavior of human players I have known. As I shift its playing strength downward I sometimes have the feeling that I em lobotomizing a thinking creature (I can even do this in the middle of a game -- a new kind of cheating). These characteristics, along with the sensory features, give it a strangely life-like effect. Also, its moves generally make sense; I've played worse real ones.

Chess Challenger's chief weakness is that it has no feel for positions, and can easily be maneuvered into total submission despite its capabilities. In its higher levels it is good at calculating complications and can be tough to beat if one is enticed into playing its kind game.

Even at the higher playing levels the device is vulnerable to errors involving the overworked piece, and consistently fails to assign a high enough priority to stopping queening pawns. In the openings, its sense of development and tempo are poor, and in the lower levels it is likely to advance its queen prematurely. When playing in the lover levels, it always seems to proceed on the principle of "Always check, it might be mate." I know guys who do that at parties.

The device gropes in position play, even in the higher levels. Unless there is some specific threat, it seems unsure about how to get counter play, and, like a duffer, it is reduced to playing with its pawns. It really gets clobbered in speculative openings, like the King's Gambit. It has a number of canned openings, but outside of these familiar patterns, it fumbles around like an innocent. Nevertheless, in tough situations, it can come up with some really good thrusts.

Knowing how much he likes artificial devices that mimic human behavior, I introduced my device to Darrell Bross at a party last New Year's Eve. It beat the socks off him on level 1. I don't think he enjoyed playing with it much. Maybe Darrell would have preferred one that talked to him. Maybe someday the Fidelity people will build a chess playing vinyl doll that says "When will I see you again?"

For the experienced player, this device seems best suited for light amusement and practice in avoiding simple blunders (it will never overlook an easy capture). Beginning players will probably find this gadget a useful, non-threatening way to build up their basic game. (On level 1 it is blind to simple checkmate threats, thus encouraging players to try such.) As the level of play increases the player needs to develop some basic strategic skills to win.

Following are some typical games to show how it reacts on various levels. I tried to play in a superficial fashion, with a simple strategy of going for a king side attack while shutting out the black pieces with pawn barriers. On level 8 and 7 it will sometimes castle queen side, completely avoiding my attack. This alternate move is apparently a product of random choice, however, and does not arise from same pre-programmed strategic sense. (The levels, in order of strength are 1-4, 8, 7, 5, 6). Level 5 is for problems and endgames and level 6 is for postal chess (with a 24 hour turnaround time). Despite the result shown, level 8 usually provides considerably more competition than levels 1 through 4.

When not staring at a chess board, John Cumming has been an officer at the local and national level of Mensa. He is also a self-described "amateur bourbon taster." He has worked as a programmer and technical writer.

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