Paul Cezanne, who produced a series of paintings featuring card players, said, “The day is coming when a single carrot, freshly observed, will set off a revolution.”

That was quite some claim, but in today’s deal East has a chance to dangle a carrot that might cause a “revolution” between North and South.

First, though, this week we are wondering when declarer should ruff and when he should discard. This is another straightforward example. South is in four hearts. West leads the club jack, and the defenders keep playing the suit. What should declarer do?

Note North’s raise to two hearts. With a weak hand, tell partner as quickly as possible. Yes, if South is 4-5 in the majors, spades could be the better trump suit. Then North hopes his partner has enough to bid higher, when South would rebid two spades.

Should declarer discard his inevitable diamond loser at trick three?

Certainly not! That would put his contract on the spade finesse, when he has 10 top tricks: three spades, five hearts and two diamonds.

Well, in theory 10 top tricks. After ruffing at trick three and drawing trumps ending in his hand, South runs the spade nine (the lowest card that can win the trick if the finesse is working). Now an East with steely nerves can dangle a tasty-looking carrot. He ducks smoothly. Then when South runs the spade queen, East ducks again! If declarer greedily assumes the finesse is winning, he will take a third finesse, but East will produce the king out of his back pocket, and the contract will go down one.