Pandolfini's Puzzler #28 - Rules, Rules, and More Rules

Professor: Good afternoon, class. Today we’re going to start by defining some terms.

Zephyr: Terms? What types of terms?

Lucian: You mean like semesters and trimesters and stuff?

Professor: Not those kinds of terms. No, I thought we would talk about rules, general rules, and rules of thumb.

Lucian: Those words sound like the same words. They’re a little different, I suppose, but don’t they pretty much mean the same things?

Professor: The way most people ordinarily employ them, the answer is “yes.” But many chess teachers have found that it’s useful to define those terms more specifically and to choose their words more carefully.

Zephyr: OK, I’ll bite, Professor. How do you choose to use those terms?

Professor: Well, I like to differentiate them. In this class, rules are something like requirements or restrictions you can count on without exception. For example, take the rules of the game. They tell us what can be done legally and what can’t be done legally.

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Lucian: Sure, like how and when you castle.

Professor: That’s right. For example, a sample rule concerning castling would be: “You can’t castle if you’re in check.” It’s a law of the game. It has to be obeyed. It’s always true.

Zephyr: So how is that different from what you call a general rule?

Professor: A general rule is something more like a principle.

Lucian: You mean like the opening principles about playing for the center and developing all the pieces?

Professor: Yes, that’s what I mean. Making a sentence of it, a general rule is a principle, guideline, or piece of advice concerning strategic play.

Zephyr: I knew that. It tells us a good thing to do or a bad thing not to do.

Lucian: So a general rule about castling would be something like it’s wise to try to castle early in the game.

Professor: That’s right. General rules essentially guide us to do the right thing or caution us against doing the wrong thing.

Lucian: Like advising us not to make unnecessary pawn moves?

Professor: Yes, just like that. That’s right. Bad pawn moves cause weaknesses and they can’t be taken back. We’re stuck with the consequences of bad pawn moves. Another point is that general rules should be observed because they usually work. But they should never be viewed as totally reliable and always true. And no matter how well they’re phrased, they can never give you your next move.

Zephyr: Okay, so tell us about a rule of thumb. What is it exactly?

Lucian: Yeah, and how’s it different?

Professor: The way I tend to use it, a rule of thumb is a practical expression. It typically encapsulates a principle in a convenient, handy, or powerful phrase or sentence. Therefore, rules of thumb often are quite short, making them easier to remember.

Zephyr: Can you give us an example of what you mean?

Professor: Absolutely. Consider the general rule advocating early castling. It can be cogently reduced to “Castle early.”

Lucian: So it seems to just be a neat way to say a principle or a general rule.

Professor: That’s right. Advice such as “castle early” or “rooks belong on open files” are short little phrases that codify sensible strategy. They don’t always work. They’re only usually true. Even so, they sound very compelling, as if they’re laws of the physical universe.

Zephyr: You mean they’re not?

Professor: That’s funny. Perhaps you’ll wind up teaching a class yourself one day. Anyway, rules of thumb can often enough be tapped to help you play better, at least up to a certain level of understanding. At some point, however, you have to go beyond generalities and get concrete and specific.

Lucian: I hate to bug you on this, Professor. But can you go over all of that again?

Professor: Sure, let’s summarize. A rule is always the thing to do. It’s always true. A general rule is typically the thing to do. It’s usually true. Meanwhile, a rule of thumb helps us remember a general rule.

Lucian: I think I’m ready for today’s puzzle.

Professor: OK, but then you better be ready for two puzzles, not just one. Please consider the following two diagrams.

White to move.

White to move.

Professor: In diagrams 1 & 2, it’s White’s turn to move. In both positions, White is up a pawn and has a much better placed king.

Question 1: For both positions, how does White force a win?

Question 2: Are both positions winning?

Question 3: Is there an interesting relationship between the defending king and how White first moves his unmoved pawn (the one starting on its second rank)?

After a mere 10 minutes, the elite class had the answer. Furthermore, Zephyr and Lucian had an explanation. They even created a rhyming rule of thumb. Now let’s see what you can come up with, taking as much time as you’d like. Your answer and explanation doesn’t have to rhyme, but it should have reason.

Answers below - Try to solve Professor Pando's puzzle first!

ANSWER #28

The situations shown in today’s column (of knight-pawn and rook-pawn vs. rook-pawn) happen more often than most of us think. So it’s a good idea to explore these positions with some care.

For diagram 1, White wins with 1. h3! – a one-square advance. By advancing the h-pawn only one square, White ensures that when the g-pawn eventually advances to the 6^th rank, White will have the opposition. A possible continuation goes 1…Kh8 2. h4 Kg8 3. h5 Kh8 4. g6 hxg6 5. hxg6 (note White has the opposition) Kg8 6.g7 Kf7 7. Kh7, and the pawn will queen.

For diagram 2. White wins with 1. g4! – a two-square advance. By advancing the g-pawn two squares, White makes sure to get the opposition when the g-pawn eventually advances to the 6^th rank. A sample variation would be 1…Kg8 2. g5 Kh8 3. g6 (giving White the opposition) hxg6 4.hxg6 Kg8 5.g7 Kf7 6. Kh7, and again the pawn queens.

In both positions, White had essentially a fixed pawn (for both positions, the fixed pawn being the one on its 5^th rank), and a movable pawn (for both positions, the white pawn starting on its 2^nd rank).

There is at least one interesting relationship and it is one of color. Let’s call it a color rule. Accordingly, if a rook-pawn is the movable pawn, White can force a win by moving his rook-pawn to the same color square occupied by the black king; if a knight-pawn is the movable pawn, White can force a win by moving his knight-pawn to the opposite color square occupied by the black king.

It can be summed up by the following rhyme:

“The rook-pawn’s the same;

the knight-pawn’s a different game.”

Take note

In pawn endgames especially, it can be very helpful to have at least one unmoved pawn. With such a weapon, a player retains the option of going either one square or two squares at a crucial moment. To that end, we see another virtue to avoiding unnecessary pawn moves. They can hurt us at any point in a game. Even early in a game, when they seemingly have no immediate impact, they can come back to haunt us much later. Indeed, a needless pawn move in the opening can mean the loss of a tempo in the endgame, possibly when it’s critically needed.