to any other piece. It does not become a queen. It becomes something else. We call this underpromotion. You have heard the term?”
“Yes.”
“Good. Because you see, Doctor, the ordinary Excelsior is child’s play, so easy that, if you are solving problems and you see the words Helpmate in five moves, the first thing you do is look for a pawn to start pushing. If the only way to force mate is for a pawn to make five moves and then underpromote-well, then you have your Excelsior.”
“I understand.” But his didacticism is beginning to wear on me, and I wonder if I am on a fool’s errand.
“Good. Because, Doctor, the Double Excelsior-ah, well, that is a challenge for the sophisticated designer only.”
“Why?”
“You have forgotten what I said before? That in a helpmate it is black who plays first and the two sides cooperate to checkmate black? The Excelsior requires five moves. So does the Double Excelsior. But there is a difference. In the Double Excelsior, each side must make all five moves with just one pawn, and, on the fifth move, both sides-first black, then white-must promote to the same piece. So, if we have a Double Excelsior with a rook, black moves first, makes five moves, and on the fifth move the pawn becomes a rook. And white moves second, makes five moves, and on the fifth move the pawn becomes a rook. And after white’s fifth move, black is checkmated-but there must be no other possible line of play leading to mate except for each side to make five moves and promote to the same piece on the fifth move. You are with me, Doctor?”
“I’m with you.”
“So, a Double Excelsior with the knight would mean that the only way for white to give mate in five moves is for both players to move a single pawn exactly five times, at the end of which both players promote to a knight, and black is checkmated.”
“But you said it’s impossible…”
“That is correct.” I have touched, finally, his pedagogic side, and he is almost patient, now that he has the opportunity to do some actual teaching. “You have to understand that the other Double Excelsiors have been demonstrated. Both players promote to a rook? Done. Both promote to a bishop? Yes. But nobody has managed to make it work with the knight. Thirty years ago, forty, something like that, a chess writer issued a challenge, and offered a significant money prize to anybody who could successfully demonstrate the Double Excelsior with the knight. But the challenge has never been answered. Lots of composers have tried, but nobody, even with the aid of computers, has managed to do it. So, most of us have come around to the view that it cannot be done.”
I frown, trying to take this in. My father was trying to solve a chess problem that the composing world believes to be impossible. His immortality? I think not: his mind was more subtle than that, unless it was as simple as Lanie Cross suggested, that he suffered a nervous breakdown and was not thinking straight. But I am not so sure. I think the Judge would have wanted more. Oh, he might have possessed the raw ambition to compose the problem nobody had ever managed. He might have dreamed of being the one to do it. But the reason he put the word Excelsior in his note to me…
“Karl?”
“Yes, Doctor?” The mocking tone has returned. Karl’s attention has wandered back to the suddenly crowded room, and therefore to his regular duty of making lives miserable. “Is there a problem? Was the explanation too complicated? Or do you perhaps resent that it is black instead of white who is checkmated at the end?” He laughs. “But in the chess problem it is always black who is checkmated at the end, is it not?” Cackling, he makes to rise.
“Wait,” I say, more sharply than I intended, as though he is a student.
Karl’s eyes widen. Very little surprises him, but my tone does. Now that I have his full attention once more, I take my time. Something he just said- it is always black who is checkmated -was that it? In the Double Excelsior, black is indeed checkmated, but… but Lanie Cross said… wait…
“Karl, look. In the Double Excelsior with the knight-I mean, if you yourself were to try to construct one-which pawn would you use?”
“Eh?”
“The pawn that becomes a knight at the end? The knight that gives checkmate? It has to start somewhere, right? So-what is it, a rook pawn, a bishop pawn, what?”
“Oh, I see. It is the white queen’s knight pawn.”
Meaning the pawn that, at the beginning of the game, is standing on the square right in front of the knight that is two squares to the left of the queen.
“Why is that?”
“In theory it should make no difference. You could use any pawn to demonstrate the theme. But when Sam Loyd developed the original, he used the queen’s knight’s pawn. So a serious composer of a Double Excelsior would honor the original by using the same pawn.”
“The… uh, the white queen’s knight’s pawn.”
“Of course the white.”
“But the white queen knight’s pawn would be the second piece to move. Black moves first.”
“Again you are correct, Doctor. Of course, in the old days, some composers designed helpmates in which white moved first, and it was white who was mated at the end.” He squeezes his jowls as though trying to shrink them. “But no true artist would do it that way. Not any more. A composer must follow the rules. It is black who must lose.”
“Still, if someone wanted to design the problem so black would win-”
“That would be silly. A waste of time. Unartistic.”
“But which pawn would move first?”
Despite himself, Karl is interested. He sighs to prove he isn’t. “Any pawn would do, of course. The true artist, however, would again use the white queen knight’s pawn. Only it would now be the black pawn, moving second, that would deliver mate on the fifth move.” He is on his feet again, surprisingly light and gay, leaping toward the narrow wooden bookcase that stands in the corner. Nobody is allowed to touch the old books, many of them in German or Russian. He selects a volume and, to my surprise, thrusts it into my hands. “Take this.” He nods with some enthusiasm. “It has many examples of the Excelsior theme. Keep it as long as you like.” This astonishing and uncharacteristic act of generosity brings a solemn hush to the dozen or so members in attendance tonight.
I know at once the book will be unhelpful. I already have what I came to get.
“Thank you, Karl, but this… it’s not necessary.”
“Nonsense. But we must protect the book, of course. Here.” He hands me an aged and torn manila envelope. “You will carry it in this.”
“Karl, I…”
He holds up a warning finger. “I have loaned perhaps three or four books in all my years in your fair city. You owe me thanks.”
And he is right. He is as controlling as ever, but he is trying to help. I do owe him thanks. “Thank you,” I say, and I mean it.
Except that Karl is now embarrassed, perhaps not sure what impulse moved him to such a kindness. I suspect it was simply his delight at finding someone-in these uncultured days, as he would say-who actually showed an interest in the area of chess he knows best, an area about which almost nobody cares. I remind myself how empty a life he leads, and I smile my gratitude even as I watch his face turn sour again. I know he is going to send me off with a fresh insult, and I know how badly he needs to do it.
“Just remember what I told you, Doctor.” His brutal laugh is back.
“The Excelsior must end with the white pawn promoting and giving mate. Black moves first in the helpmate, remember, but it is still white who gives mate at the end. Always white.” He falls silent and regards me suspiciously, as though no longer sure I have come to his club on legitimate business. He leans close, his tiny fists pressing on the table in front of me. “We cannot change the way of the world over the chessboard, can we, Doctor?” Chuckling at his success in getting in the last word, Karl wanders off to torment somebody else.
I am glad to be rid of him. I hang around for another half-hour, watching a couple of games and playing a couple of games, and then, carrying Karl’s book in its protective envelope, I slip out into the frosty night.
Excelsior, my father wrote, and he repeated the word. It begins! Neither the popular Addison nor the social
