Overcoming the Power of Suggestion


I am a mediocre poker player and doubt I could become a good one even if I worked hard at it, which I have no interest in doing. I play because it’s fun, and I keep the stakes low enough that I don’t mind that I usually lose. Also, I find poker enjoyable to write about in terms of human psychology, for example how a logical puzzle about a poker game has analogies to difficult romantic relationships and how a memorable bad luck outcome can tempt us to revise decision rules that are in fact generally reliable. I played in a hand not long ago that fascinated me in terms of the power of suggestion.

In a Texas hold ’em game of eight players, the flop was unusual: 9 of diamonds, 10 of spades and Jack of clubs, in that order. It looked like the dealer was laying down a straight on his own, and even though the order of the flop cards is irrelevant, the fact that the cards came in sequence made it even harder for everyone not to be thinking straight straight straight.

One of the players was in heaven. He had taken a risk by staying in for the flop during the first round of betting with only an 8 and Queen of hearts. With a straight to his name now, it would be very hard to lose and he bet with confidence. Two other players kept betting up to the turn card, which came up a 4 of clubs. One player folded at that point despite having a not bad hand (a 10 of diamonds and Ace of hearts), because he assumed based on the flop that for the other two players to be staying in and betting significantly, there was at least one straight in the offing.

The river card was a Queen of spades. The player with the straight groaned inwardly, but then went through the possibilities for a straight the other remaining player (me) might have. If I had a 7 in the hole and had been hoping for an 8 or had a Queen in the hole and has been hoping for an 8, I was out of luck. In the unlikely event that I was holding an 8 and had been hoping for a Queen (unlikely because he had one of the 8s), it would be a split pot: no tragedy.

He said out loud “The only way I can lose is if you were stupid enough to have a king and be hoping since the flop that a queen could come up”. I took it as a compliment that he bet big after saying this, because it would indeed have been foolish to expect to fill an inside straight like that.

I called his big bet and he turned over his straight. I turned over a king, for a higher straight. Care to guess why I stayed in?

As you might have guessed, my other card was also a king. The flop mentally suggested straight very strongly and of course so did the other player’s own hole cards, so it was cognitively hard for him to break out of that mental frame and realize that I might have been just playing a pair of kings. When the flop came up as it did, I knew my kings would beat anyone who had paired one of the flop cards, so I stayed in. I realized that I would lose to a 7 and an 8 or an 8 and a queen in the hole, but that seemed very unlikely (Even though of course it happened), and I obviously didn’t have to worry about someone holding an 8 in the hopes of landing a queen on the turn or river.

The guy I beat on this hand is a better player than I am. I would have done what he did and lost like he did if not worse. It’s very hard for any of us to not go inexorably down a particular line of reasoning when all signals seem to be pointing there so strongly.

[Cross-posted at The Reality-Based Community]

Keith Humphreys

Keith Humphreys is a professor of psychiatry at Stanford University. He served as a senior policy advisor at the White House Office of National Drug Control Policy from 2009 to 2010.