Card Sense

People who are good at playing one game are often good at others. In particular, there seems to be a general ability, sometimes called “card sense”, that seems to enable a player who is good at one card game to excel at other card games.

Card games may have this distinctive skill because of the way that almost all card games, and very few other games, incorporate the element of chance.

Consider the difference between the way card games and dice games operate. Dice are very straightforward randomization devices. At any point in the game, the odds of getting a certain number from the roll of a standard six-sided die are fixed at one in six.

There’s a natural human inclination to think that dice get “hot”, yielding disproportionately many good numbers. They don’t. But some of the same gamblers who make this mistake also embrace the contradictory notion that when the dice get “cold” they must be “due” to produce good numbers soon, which is equally untrue. Dice have no memory, and remain predictably unpredictable. The better players of dice games know this, and resist the inclination to read moods and tendencies into the behavior of the dice.

Cards are different. A deck of cards, seen as a randomizing device, does have a memory – each card dealt alters the odds on the next card. This effect grows as the deck diminishes. When all but one of the cards is dealt, there is no random element at all as to what remains. In many card games there is indeed such a thing as a “hot” deck (or a cold one). Adjusting one’s play accordingly is a skill to be cultivated rather than temptation to be resisted.

It is this steady decrease in the entropy associated with the deal that gives card games, and a few other games like Scrabble and dominoes, a distinctive feel. Over the course of a hand, the game reveals itself, little by little.

What we recognize as card sense, I suggest, is mostly the ability that some players acquire to absorb this new information. The player with good card sense does this more quickly and more accurately than other players, who find it harder to adjust their expectations away from the probabilities represented by the initial distribution of the cards.

The way that good players exploit their card sense varies considerably from one game to another, and in coming posts I’ll explore some of those differences.