Bridge inculcates one to think logically. The cards always lie randomly silent if the opponents don't reveal them through their bidding. This makes the task of the declarer not an easy one. At times when the play dictates several options open for consideration, the declarer weighs the pros and cons of each and selects the one where he feels his risk of going down is at the minimum. Of course good judgement is an advantage if you can use it consistently to success. But in Bridge there is the factor of how tough the opponents are in their defence. Good opponents rarely give you the easy route to success. They always strive to make your life as difficult as possible.
To counter such moves of the opponents, a good declarer needs imagination and foresight. He has to be alert to the adverse break of suits and think logically to pick the right inferences that could well be the guide to steer the declarer safely through the haze of multiple choices in enabling him to make his contract.
Today's illustration is a problem in logic and can become perplexing if the declarer is not attentive to what is the need of the hour. The easier a problem looks, the tougher it becomes to solve it ultimately. On the following deal NS reach 6NT as under.
The bidding
The opening lead is JS. As south can you plan to make this contract with a hundred percent guarantee and without taking the least risk? Let us turn our attention to the available tricks for the declarer. There are 8 solid tricks to start with needing 4 more to be developed either from the diamond or the club suit. The vital question is which one to pick and why? Playing a slam one needs to be careful at each step. What does the dummy offer? At least 5 tricks presuming the diamond king is off side. That would give you 5 diamonds plus 3 spades plus 2 hearts and 2 clubs for 12 tricks required. Alternately the club suit offers 5 tricks provided the QC is not under finesse which added to the 5 major tricks available plus the ace of diamonds adds up to only 11 tricks. So it seems the diamonds offer a better choice to toe the line for the slam to make. But what about the snags that the opponents would place to prevent you for an easy sailing. It would be a baby play to win QS in hand, play AD and back toward the QD praying that the opponents takes his KD to give you your contract on a silver platter. But the opponents are nasty and non-co-operative. What if the opponent refuses to cash his KD? Then you are short of entries in dummy to run the diamonds and your only hope then would be a successful club finesse which if it fails would sink you in a contract that otherwise on the face of it is unbeatable.
As south did you think logically to arrive at the solution which would then appear to be so easy? Yes, the key play is to hold on to the AD and play the QD first after taking the opening lead of the JS in hand with the queen. This guarantees you 12 tricks come what may. If west takes the KD you have your easy 12 tricks. If he allows QD to hold you get your extra trick in diamonds and can now resort to the club finesse getting all 13 if it succeeds and the required 12 even if it does not.
Ah ha! What about the counter defence? What if east takes the KD and knocks out the spade entry in dummy cutting communication between the two hands with the diamond ace still blocking the suit from running. No problem! Just discard the ace of diamonds on dummy's ace of spades. That's it. All that was needed was the imagination to throw an ace on ace!

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 North          South
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    AK7            Q3
     32           AK4
     43            AQ
J109843       AKJ1094
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  S       W        N       E
 2C       P       2D       P
 3C       P       3D       P
4NT       P       5D       P
5NT       P       6S       P
6NT                 ALL PASS
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