Morton’s Fork
Named after Cardinal Morton, King Henry VII's Lord Chancellor, because of his method of extracting taxes from merchants. If a merchant lived ostentatiously then Morton averred that the merchant could afford to pay more. Alternatively if a merchant lived frugally then the merchant must have saved enough, and similarly could afford to pay more. Either way, the merchant was impaled upon Morton's Fork.
Despite living long before the advent of Contract Bridge, Morton and his fork have become synonymous with a maneuver whereby declarer gives a defender two options, neither of which is good for the defence.
In today's hand declarer is in 3 NT after West has opened 1 ♠. South's reopening 1 NT showed 11-16 high card points and North just raised to game. West decided to lead a heart and struck declarer's weak point. As declarer, let's count our tricks and make a plan. There are seven tricks after the heart lead: one spade, two hearts and four diamonds. Spades and clubs will almost certainly generate the two tricks required.
Who led a spade? It certainly looks right doesn't it, but did you think about the play. You can't guarantee setting up your second spade trick without losing a spade trick. If both the king and queen of spades are in West's hand then West simply plays one when you lead a spade, and if the king and queen are split between West and East then your first finesse will lose to East. Upon losing a spade, the defenders will knock out your last heart stopper, and when you try to get a club trick the defenders will take their ace and cash at least three heart tricks for one off.
What about clubs? Given East's pass of the opening bid, the club ace is almost certainly in West's hand. What happens if we lead a club from South through West towards the king? West can play play low and we will win the king and, having got our club trick, we can come back to the South hand and play on spades. Alternatively West can win the club ace and clear the hearts but now we will have two club tricks and only need one spade trick, which we have.
Poor West, well and truly impaled on Morton's Fork.