meanwhile the happy little man had edged them into the first of a small cluster of tables, where a dark-suited jabbering trio was just rising. he snapped his fingers and hissed through his teeth. a white-aproned waiter materialized.
"for myself black coffee," he said. "for mademoiselle rhine wine and seltzer?"
"that'd go fine." sandra leaned back. "confidentially, doc, i was having trouble swallowing ... well, just about everything here."
he nodded. "you are not the first to be shocked and horrified by chess," he assured her. "it is a curse of the intellect. it is a game for lunatics—or else it creates them. but what brings a sane and beautiful young lady to this 64-square madhouse?"
sandra briefly told him her story and her predicament. by the time they were served, doc had absorbed the one and assessed the other.
"you have one great advantage," he told her. "you know nothing whatsoever of chess—so you will be able to write about it understandably for your readers." he swallowed half his demitasse and smacked his lips. "as for the machine—you do know, i suppose, that it is not a humanoid metal robot, walking about clanking and squeaking like a late medieval knight in armor?"
"yes, doc, but...." sandra found difficulty in phrasing the question.
"wait." he lifted a finger. "i think i know what you're going to ask. you want to know why, if the machine works at all, it doesn't work perfectly, so that it always wins and there is no contest. right?"
sandra grinned and nodded. doc's ability to interpret her mind was as comforting as the bubbly, mildly astringent mixture she was sipping.
he removed his pince-nez, massaged the bridge of his nose and replaced them.
"if you had," he said, "a billion computers all as fast as the machine, it would take them all the time there ever will be in the universe just to play through all the possible games of chess, not to mention the time needed to classify those games into branching families of wins for white, wins for black and draws, and the additional time required to trace out chains of key-moves leading always to wins. so the machine can't play chess like god. what the machine can do is examine all the likely lines of play for about eight moves ahead—that is, four moves each for white and black—and then decide which is the best move on the basis of capturing enemy pieces, working toward checkmate, establishing a powerful central position and so on."
"that sounds like the way a man would play a game," sandra observed. "look ahead a little way and try to make a plan. you know, like getting out trumps in bridge or setting up a finesse."
"exactly!" doc beamed at her approvingly. "the machine is like a man. a rather peculiar and not exactly pleasant man. a man who always abides by sound principles, who is utterly incapable of flights of genius, but who never makes a mistake. you see, you are finding human interest already, even in the machine."
sandra nodded. "does a human chess player—a grandmaster, i mean—ever look eight moves ahead in a game?"
"most assuredly he does! in crucial situations, say where there's a chance of winning at once by trapping the enemy king, he examines many more moves ahead than that—thirty or forty even. the machine is probably programmed to recognize such situations and do something of the same sort, though we can't be sure from the information world business machines has released. but in most chess positions the possibilities are so very nearly unlimited that even a grandmaster can only look a very few moves ahead and must rely on his judgment and experience and artistry. the equivalent of those in the machine is the directions fed into it before it plays a game."
"you mean the programming?"
"indeed yes! the programming is the crux of the problem of the chess-playing computer. the first practical model, reported by bernstein and roberts of ibm in 1958 and which looked four moves ahead, was programmed so that it had a greedy worried tendency to grab at enemy pieces and to retreat its own whenever they were attacked. it had a personality like that of a certain kind of chess-playing dub—a dull-brained woodpusher afraid to take the slightest risk of losing material—but a dub who could almost always beat an utter novice. the wbm machine here in the hall operates about a million times as fast. don't ask me how, i'm no physicist, but it depends on the new transistors and something they call hypervelocity, which in turn depends on keeping parts of the machine at a temperature near absolute zero. however, the result is that the machine can see eight moves ahead and is capable of being programmed much more craftily."
"a million times as fast as the first machine, you say, doc? and yet it only sees twice as many moves ahead?" sandra objected.
"there is a geometrical progression involved there," he told her with a smile. "believe me, eight moves ahead is a lot of moves when you remember that the machine is errorlessly examining every one of thousands of variations. flesh-and-blood chess masters have lost games by blunders they could have avoided by looking only one or two moves ahead. the machine will make no such oversights. once again, you see, you have the human factor, in this case working for the machine."
"savilly, i have been looking allplace for you!"
a stocky, bull-faced man with a great bristling shock of black, gray-flecked hair had halted abruptly by their table. he bent over doc and began to whisper explosively in a guttural foreign tongue.
sandra's gaze traveled beyond the balustrade. now that she could look down at it, the central hall seemed less confusedly crowded. in the middle, toward the far end, were five small tables spaced rather widely apart and with a chessboard and men and one of the siamese clocks set out on each. to either side of the hall were tiers of temporary seats, about half of them occupied. there were at least as many more people still wandering about.
on the far wall was a big electric scoreboard and also, above the corresponding tables, five large dully glassy chessboards, the white squares in light gray, the black squares in dark.
one of the five wall chessboards was considerably larger than the other four—the one above the machine.
sandra looked with quickening interest at the console of the machine—a bank of keys and some half-dozen panels of rows and rows of tiny telltale lights, all dark at the moment. a thick red velvet cord on little brass standards ran around the machine at a distance of about ten feet. inside the cord were only a few gray-smocked men. two of them had just laid a black cable to the nearest chess table and were attaching it to the siamese clock.
sandra tried to think of a being who always checked everything, but only within limits beyond which his thoughts never ventured, and who never made a mistake....
"miss grayling! may i present to you igor jandorf."
she turned back quickly with a smile and a nod.
"i should tell you, igor," doc continued, "that miss grayling represents a large and influential midwestern newspaper. perhaps you have a message for her readers."
the shock-headed man's eyes flashed. "i most certainly do!" at that moment the waiter arrived with a second coffee and wine-and-seltzer. jandorf seized doc's new demitasse, drained it, set it back on the tray with a flourish and drew himself up.
