The Culbertson forcing system

R. J. LEIBENDERFER

ELY CULBERTSON

The second of a series of articles on the new and scientific system of bidding at Contract Bridge

■ EDITOR'S NOTE: In the May issue of Vanity Fair a general picture of what the Culbertson Forcing System is, was presented. The article was necessarily brief. This second paper in the series is intended to take the reader one step further.

The Forcing Principle

■ The Forcing principle is a logical and necessary extension of the Approach principle, with the added proviso that, in certain situations, both partners are required to keep the bidding unconditionally open until a game bid is selected.

The reason for the Forcing bid is that: The majority of strong hands contain a choice between one or more suit bids and no trump; a game (and sometimes Slam) is assured provided neither partner passes before the best fitting bid is selected.

To illustrate: With this hand:

the selection of a successful game bid hinges upon partner's hand distribution. The opening two spade bid will eventually force a choice of one of four bids—spade, heart, diamond or no trump. The distribution which best fits in with partner's hand will be the deciding factor. Any other so-called "common sense" method shuts out better bids (if a game is contracted for) or risks being left in (if a game is not contracted for).

■ Again: Partner having opened with a one club bid—an acrobatic—and you hold:

the combined strength of the two hands guarantees at least a game at some bid, always provided that the best combination is selected. Without the Forcing Principle the bidding is, at best, a choice of evils: one spade, or any other "normal" take-out, risks that partner may drop the bidding, and any direct game bid automatically (and often disastrously) shuts out all other bids. Hence the indispensable "Jump" Takeout, in a new suit, which is Forcing—a bid of three diamonds over your partner's one heart, etc.

There are two situations in which strong hands containing a choice of bids occur:

(a) When great honor strength is concentrated in a single hand;

(b) When great honor strength is divided between the Opening and Responding Hands.

To meet the former situation the Opening (Forcing) two-bid in a suit is used. The twobid is nothing more nor less than a gigantic Approach bid. For the latter situation—by far the most important and common—the Forcing Take-out is used by either partner.

Finally, there is a third type of Forcing bid which is applicable at all stages of bidding. This third Forcing bid is an Overcall in a suit which has been previously bid by opponents.

Hands containing even 4 honor tricks will not, as a rule, make a game unless partner holds about 1½ honor-tricks in addition. Hence, with all such hands, Opening one-bids will serve the same purpose, without the added disadvantages—inherent to all high bids—of crowding the bidding and shutting out partner's free responses.

It should, perhaps, here be explained that the minimum requirements for Opening suit bids of two are:

Minimum trump length: Any biddable fourcard suit.

Minimum honor-trick strength: Five honor-tricks in three suits. With freaks or long, solid trump suits 4½ honor-tricks in three suits suffice. With distributions 5-3-3-2, 4-4-3-2 or 4-3-3-3 at least 5½ honor-tricks in three suits are required.

If the bid suit has four cards, it must be headed by at least A Q, A J 10 or K Q 10 (1 ½ honor-tricks). Necessary outside honor strength, 3½ to 4 in two suits.

If the bid suit has five cards it must be headed by at least K or Q J (½ honor-trick). Outside honor strength, 4½-5 in two suits.

All Opening suit (not no trump) two-bids are Forcing and, when there is no intervening bid by the opponent, unconditionally demand a bid from partner.

For this reason practically all of the very powerful hands in Contract are started with two-bids in order to secure the advantage of precise information from partner's various responses at a low stage of bidding.

The characteristic feature of Opening suit bids of one and two is that whatever their honor strength, the trump suit is apt to be shaky and so requires, as a rule, definite trump length and strength in support from partner. Furthermore such hands are usually of a flexible type, that is, they offer a choice among several possible bids.

Opening Bids of One

Opening one-bids in all suits or in no trump, require and show at least 2 1/2 honor-tricks as Dealer, or after one pass (position of First or Second Hand); and 3 honor-tricks after two or three passes (position of Third or Fourth Hand).

When vulnerable the hand should be a Queen stronger than such minimum, or the trump suit longer. In all other respects—the state of score, personal equation, etc.—the minimum requirements for Opening bids are not affected.

When opponents have a part-score and are not vulnerable the Last Hand should avoid opening on 3 bare tricks.

An Opening bid is the best defense. To pass, when able to open, will misinform partner quite as much as to make an opening bid without minimum honor values.

The Responding Hand

The partner of the Opening Hand is called the Responding Hand. In the Forcing System the Responding Hand, far from merely assisting, is in most cases the principal hand and carries the brunt of bidding. As a rule the game, or Slam value of the Opening Hand, is relative and depends upon the distribution and balance of honor strength in the Responding Hand. Accordingly the whole scheme of Contract bidding is so designed that the Opening Hand, whose first bid is necessarily a leap in the dark, "approaches" with low bids and feels out the situation before definitely choosing the attacking or defending direction.

■ The requirements for a pass are (assuming partner has opened with a one-bid) :

1. Any hand which contains no raise, no biddable suit, and less than 1 ½ honor tricks.

2. Any hand which, though containing a minimum biddable suit, has less than I honor trick.

Raises on "freak" distributions are excepted.

A hand which contains 1½ honor-tricks, or a fair suit with but 1 honor-trick, is a responding hand and requires some sort of response other than a pass.

The secret of partnership bidding revolves around a simple question: Has my hand some new fact, some definite value which my partner does not logically assume or of which he is not aware from previous bidding? If my hand does contain some element which my partner has not assumed, I speak up. If my story has been told already or is inferentially known to partner I keep silent. In the rigidly intellectual language of bids, meaningless repetition or unjustifiable silence is equally fatal!

The Responding Hand also passes when its strength is below expectations; makes a minimum response when the hand is somewhat better than the Opening Hand has a logical right to assume; and jumps the bid, flashing a possibility of game or Slam, when his hand is considerably better than the Opening Hand has a logical right to assume. In this manner both the Opening and Responding Hands start with a definite set of "bidding minimums" and assumptions and, as the bidding unfolds itself, build up their structure of inferences.

There is a very important exception to the general principle above:

When the player on the left of the Opening one-bid passes, the Responding Hand must keep the bidding open by bidding one no trump with hands containing as little as 1 ½ honor-tricks or by giving a shaded "raise". Such hands are but an average expectancy and theoretically should be assumed by the Opening bidder. Nevertheless, they must be bid in order to afford another opportunity to the Opening Hand whose values necessarily range from 2 ½ to 5 honor-tricks, or who may easily have another and better bid:

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Such one no trump responses merely inform partner that:

(a) The hand contains insufficient trump support for the bid suit.

(b) The hand contains no other biddable suit.

(c) The hand contains but a minimum honor strength (1 ½-2 honortricks)—otherwise the response would be two or three, and not one no trump. The "negative" one no trump is an indispensable corollary to the Approach principle and the backbone of the Forcing principle.

With thousands of hands a player is practically assured of a game somewhere; but, holding a choice of several equally probable bids, he does not know which one will best fit in for game with partner's distributional values. If either partner, when holding a strong hand, can be certain that the bidding will, in all circumstances, be kept open, two and frequently more alternative bids can be offered at a low stage of bidding.

Hands so powerful that not only game is assured but a Slam is definitely in sight, are additional reasons for Forcing bids. Through Forcing bids, one obtains from partner, and conveys to him without risk, information as to the distributional and honor values of his hand which is of vital importance in successful game and Slam bidding. The assurance that partner will not pass too soon—and this is the fundamental condition of all Forcing bids —makes it possible to unravel, through a series of precise inferences, the distributional and honor values of partnership hands which, in Slam bidding, is vital.

(To be continued in the next issue)