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During my post-doctoral years I played poker very seriously. For a while, my poker library grew much faster than my psychology library, and I became a profitable mid-level player. I have played very little since my post-doc ended, but I think the experience was valuable. For one thing, the mathematics of poker is fascinating, and I still nurture a hope of one day teaching a "Statistics of Poker" seminar. For another thing, I think poker provides an excellent context for thinking through theories of psychology. On the surface, poker seems like it is a game about cards, and on the surface it is. However, you don't need to get much below surface-level to see that poker is primarily a game about the behavior of the other players. The player on your right just put in a big bet: Does he have a big hand? Is he bluffing? What does he think you have, and how does he think you will respond? Given what he might have and what he thinks you might have, if you put in a huge re-reraise, how will he respond? The layers of analysis that can be applied to these situations is fun, but not really on topic for this post (though I talked a little about it here). Instead, I want to delve into a very typical poker situation from the point of view of a psychological realist vs. a dualist.
Note that this is a preliminary analysis that I hope to develop further, and I would love any feedback.
A Single Hand
To keep the situation simple, we will be watching the most popular poker game of the moment, No-Limit Texas Hold'um. No-Limit Hold'um went from obscurity to ubiquity when some reportersrealized that it made for great television, especially when the audience at home can see the players hidden cards. In this game each player gets two hidden cards, and there are five cards placed face up on the table (through a series of reveals). Each player makes the best five-card hand she can out of the seven cards available to her. For now, we will fast forward to the end of a hand between two players, and use an example where the suit of the cards don't matter.
- Player 1's face-down cards: 7, 8
- Player 2's face-down cards: Jack, Queen
- Face-up cards for either to use: 7, 6, 5, Ace, King
Here, at the end, Player 1 has the best hand, a pair of 7s. Player 2 has the worse hand, with a high card (i.e., nothing).
However, the hand started out with a full eight-person table, and Player 2 has been betting aggressively. Thus it might seem likely, to an live observer, that Player 2 either had a good pair to begin with, or that he connected to one of the last two cards, and now has the best hand. Thus, there is room for both players to make some interesting moves.
Now we need some basic terminology:
A bluff is a bet with the worst hand. Poker players intentionally bluff when attempting to trick an opponent into folding the best hand. (There are other game-theoretic reasons to bluff, but we'll let those go for now.)
A value bet is a type of bet with the best hand. Poker players value bet in hopes their opponents will call the bet and give them more money.
In this, the final round of betting, Player 1 leads out with a large bet. For simplicity, let us say there is $100 in the middle already, and that Player 1 bets $50.
Let us look at this situation from the two major approaches to psychology 1) a dualistic, information-processing position and 2) a psychological realist position.
Dualistic, Information Processing
For the players, in the moment, poker is certainly a game of limited information, and so the information-processing model can take us pretty far. Neither player knows the other players face-down cards, but each can guess based on the other player's behavior. Thus, while neither player knows exactly where they stand, they have probabilistic cues from the patterns of betting within this hand, from the patterns of betting in past hands, and from any "tells" they can pick up by observing their opponent carefully.
In this case, Player 1 is in the same position as a live observer in the room. She is forced to guess at what Player 2 has, and an evaluation of the available "information" leads her to believe she is likely to be beaten. However, she bet anyway. If you asked her why she bet, she would tell you that she was bluffing, and hoping that Player 2 will fold his hand and give her the $100 pot. From a dualistic perspective this is all fine and good. We can never know exactly what Player 1 is doing, but Player 1 knows perfectly (literally, perfectly), and if she says she is bluffing then by God that is what she is doing. Another way to put this is that from a dualistic perspective bluffing is a "state of mind", and she is bluffing. If we wanted to increase our confidence that her verbal report was accurate, at best we might try some careful brain scanning, because the truth is to be found somewhere inside her head.
Thus, from this point of view, we think that it is Player 2's job to try to "get inside the head" of Player 1, so that he can determine that she is bluffing. However, in this case Player 2 knows that he has nothing but a high card, and that therefore he is probably beaten. If he simply calls the $50 bet, there is little doubt that his is handing over free money. His choices are either to fold and give up the money already in the pot, or to try to re-raise the bet and bluff Player 1. The correct decision, the one with the best long-term expected value, can be determined by a bunch of math that we don't need to worry about here. The point is that from a dualistic point of view Player 2 cannot possibly know what Player 1 is thinking, as even the best-case scenario is considered analogous to the game of limited information he is stuck in by happenstance.
Psychological Realism
The major claim of psychological realism is that mental states (processes, events, or whatever you might want to call them) are observable features of the world. That is: Given enough knowledge of the world -- knowledge of what is happening now and/or of the person's behavior across other situations -- you can know what they are doing. For certain. The most provocative way of saying this is that "You can see their minds." A less provocative way of saying it would be to list contrasting mental traits, i.e., "You can know if they are remembering or imagining, paying attention or daydreaming, intending to succeed or failing, trying hard or going through the motions, value-betting or bluffing." The analysis of the above situation from the perspective of a psychological realist has, I would argue, certain advantages.
Poker, if all the cards were face up would be boring for most players, but it turns out to be great fun for a viewing audience at home. The main technological innovation that lead to the "poker revolution" about 15 years ago was the "hole camera", which allows the viewing audience to see the players face down cards. This allows you to see how the best players play, but more importantly, it allows the viewer to get outside of the limited-information game that the live players are stuck in. This highlights the "psychological" game that is being played.
A person at home, who can see all the cards, knows things that the players do not. For example, this person knows that Player 1 is not bluffing. From a realist perspective, bluffing is a doing under a particular circumstance, and as Player 1 does not have the worst hand, Player 1 cannot possibly be bluffing. We might speculate as to whether or not Player 1 is "trying" to bluff, and to determine that we would compare Player 1's behavior in this circumstance to her behavior in situations that were bluffs, but in no case is she bluffing now. No matter what Player 1 was trying to do, she was, in fact, value betting. As such, assuming this play is part of a larger pattern designed to take Player 2's money, then Player 1 wants Player 2 to call.This is true no matter what she "thinks" she wants, i.e., what she would verbally report she wants.
Wait, Why Does This Matter?
It matters because the realist approach provides a language that allows you to talk about many important phenomena than are difficult to talk about in dualism-land (also the realist approach is correct, but that isn't the big issue right now). In this case, it allows us to talk about how Player 1 was wrong in thinking that she was bluffing, when in fact she was not. A third party observer, able to see the face-down cards would have accurately reported that she was not bluffing.
Leaving the poker context for a minute, this is the same realist perspective that might allow a therapist to tell a client that they care about someone they claim not to care about. The therapist, as an observant third party, can potentially see the patterns in the client's behavior that the client does not see, or does not want to admit to. Returning to poker it is the same perspective that allows us to tell the difference between the poker player who is striving to make the most money, versus the player trying to win the most hands, versus the player trying to avoid being embarrassed, etc.
Poker provides a good contrast between 1) our understanding of other people's behavior based on the situation we might be stuck in at the moment, and 2) the understanding of other people's behavior we could have with a wider view of the world. In live poker this difference is palpable every minute, as a gust of wind blowing the player's cards faced up would quickly reveal the reality of the situation. The difference is even more obvious now that televised poker allows viewers at home to see what is going on while keeping the players in the dark.
Crucially, the person watching on TV, who can see the face-down cards, knows what is happening better than the players themselves. Player 1 might think she is performing a bluff, but the people watching TV know that she is not. Player 1 might think that Player 2's long pause before folding indicates that he considered calling the bet, but the people watching TV know that it is just a deceptive show to hide weakness. The dualistic model assumes that we are inherently, by the nature of the universe, stuck in the position of the players at the table; we cannot escape playing the guessing game with regards to the state of world, and particularly the state other people's minds. The realist model assumes that we could, if were in the right situation, directly perceive the state of the world, including knowing what other people are doing, in the broader, mental sense. Because the other person might not be observing carefully enough, or might not be sensitive to the right variables, or might not have access to the necessary point of view, it is in principle possible for us to know what another person is doing better than they know themselves.
While this is just a quick sketch, it shows the potential for the poker table to serve a s a context for such analyses. What do you think?
