The Intermediate Cube
Ted Barr, 1980
Gammon Magazine, Winter 1980

Ted Barr
So many new players have questions regarding the cube I am devoting this column to the considerations essential to cube strategy.

In my opinion the cube must always be used when playing backgammon. Whether you play for money, points, or "who does the dishes," the cube maximizes the excitement, eliminates the cat-and-mouse aspects, and heightens the skill level for effective strategies. If your mistakes are costly, it is not likely you will repeat those same mistakes often.

Knowing when to accept or decline a double is the essential measure of skill among backgammon players. Some players' theory of doubling is to accept the cube only when you are the favorite, and to offer it only when you are winning the game. Anyone who believes this theory is naive, and must consider a number of factors when determining how to handle the doubling cube.

Generally, in the early to middle stage of the game, you should have a three-roll lead before considering a double. Your opponent, by the same token, should also have a three-roll lead before offering the cube to you. If he does not, you probably should accept.

Diagram 1.
Should White double?
At a late stage of the game a one-roll lead can be sufficient to double. With few rolls left there is less likelihood of a reverse in position. In Diagram 1 White has a half-roll lead, and it is his turn to roll. Should he double? Absolutely!

It is late in the game. A half-roll lead is commanding since Black must roll doubles on one of his next two rolls to win. If White fails to double here, he gives Black the free opportunity to roll doubles. Furthermore, Black may only have one more roll if White rolls doubles.

White should use the cube to force Black out of the game and eliminate the possibility of his getting lucky. Black should decline, since to double the stakes in the hope of a long shot (rolling doubles) would be ridiculous.

Another factor which bears consideration in doubling is your position on the board, which is just as significant as your lead in the race. A substantial lead in the race will not win if, as a result of your board position, your lead dissipates.

Diagram 2.
Should White double?
Diagram 2 illustrates the importance of analyzing your position on the board. Here White holds a commanding five-roll lead, but should he double?

Although White has an adequate lead, his concern at this point is escaping. If he does not escape within the next three turns he will most likely lose the game.

As Black brings more of his men around, he will have the additional builders to put White on the bar and close his home board. Even if Black fails to hit, failure to escape will result in the dissipation of White's own home board, with three negative effects.

First, until his runner escapes, any large numbers rolled by White will be wasted. This is like taking away a portion of his turns.

Second, if White should hit Black later in the game, White will not be able to contain him long enough to escape, since his home board will be virtually wide open.

Third, if White does hit Black, it may result in White's having a man hit when Black re-enters from the bar.

Remember, when determining whether or not to give your opponent the cube, it is critical that you be aware of your position on the board as well as your lead in the race.

Another factor to consider is the position of the cube. By position I do not mean whether the cube is on 2 or 8 or whatever. I mean who owns it. Possession of the cube is most significant because whoever owns it controls the stakes or points for which the game is being played.

When the game begins, either player may double his opponent. Since you may double orbe doubled, you are not giving up exclusive access to the doubling cube.

However, when the cube is in your possession (by virtue of an earlier double by your opponent) you must be more conservative about doubling as you are also giving up the exclusive control of the cube.

Diagram 3.
Should White double?
An example of this distinction can be seen in Diagram 3. White has an advantage in the game. Should he double?

Yes, if the cube is neutral (in the middle). He does not own it, and therefore, by doubling is not giving up exclusive control of it. But, if White does own it (it is on his side of the board) he should not double. He has only a slight advantage and giving up exclusive control of the cube is not yet justified.

Exclusive control of the cube is valuable. Guard it zealously by not making a loose double. If you possess the cube and the game goes well, you can increase your wealth or point position in the match by doubling. If the game turns sour, you can play it out at no additional premium, and hope your opponent makes a mistake or that the dice turn your way. To have these options you must own the cube.

Finally, when dealing with the cube, consider your opponent's attitude. If he is leery of the cube and tends to turn down your doubles when you have only a slight advantage, by all means double him, force him out when your advantage is very slight.

If on the other hand, your opponent is stubborn and finds it difficult to decline your doubles, you can afford to wait until you have a commanding lead before doubling. He will still accept. So make sure you want him to accept before offering the cube.

Observing certain characteristics in your opponent's game can give you a tremendous edge. Nearly all games of skill reward the player who observes his opponent's behavior. In poker you analyze your opponent's betting habits. In bridge, you should consider your opponent's bidding ability. In golf, you look for the weakness in your opponent's game, be it putting, stamina, or whatever. In backgammon, the player who observes his opponent's doubling habits or even his game turns sour, you can play it out, at no additional premium, and hope your routine strategy moves has a marked advantage over the player who just plays his own game, oblivious to the playing patterns of his opponents.

Until you have taken all of these factors into consideration, you are not totally prepared to accept or decline, offer or withhold the doubling cube. If however, you weigh these factors carefully, your doubling cube play will most likely be more effective than your opponent's.

Remember, the experts use the doubling cube so effectively that even if they forfeit three games out of four, they make it all back — and then some — in the few games they win.