In The Theory of Poker
, David Sklansky introduces his “Fundamental Theorem of Poker”:
Every time you play a hand differently from the way you would have played it if you could see all your opponents cards, they gain; and every time you play your hand the same way you would have played it if you could see all thier cards, they lose. Conversely, every time opponents play their hands differently from the way they would have if they could see all your cards, you gain; and every time they play their hands the same way they would have played if they could see all your cards, you lose.The primary problem with this formulation of poker strategy is that it requires you to step outside the game. Specifially, it measures the appropriate response in terms of parameters which are not available during the game. Once you know what hand your opponent holds, it’s not poker anymore. It might be an interesting game, but by removing the element of the unknown, you’ve removed an essential aspect of poker.
This leads to a vivid contradiction between the FTOP and the practice of playing poker. When you are actually faced with a decision in poker, you must take all the information that you have at hand, and make a decision. There are many ways of formulating the correct action, but none of them allow you access to unknown information (without cheating). In the absense of specific player knowledge, the ideal tool to use is game theory.
Game theory is a branch of mathematical analysis developed to study the decision making in conflict situations. One unique feature of game theory is that when solving a problem, the agents in the conflict are assumed to be fully rational. In other words, your poker opponents play as well as you do. There are no fish in the game theory model, only sharks.
Specifically, once a game theory solution has been found, if both players play according to the strategy, they will break even in the long run, assuming there is no rake. Any deviation from that strategy by either player will result in that players expectation dropping to a negative value.
Using this sort of framework, there are certain classes of poker problems which become solvable. For example, heads up no limit hold’em can be solved in an optimal game theoric manner if you assume the players are restricted to either folding, or going all-in as their first option. Aproximate solutions have been published by several people, including the Jones/Kittock system, and Tysen Streib. And a complete solution has been published by Alex Selby.
As an example of how to use the system, let’s consider the specific scenario of what each player should do when they each have 20 chips. The blinds are 1/2, and the small blind looks down to find 98s. In accordance with the optimal solution, he jams. The big blind looks down to find T8o. Facing the all-in jam by the small blind he consults the optimal solution, and finds that he should fold, and does so correctly, despite the fact that he is better than a 2:1 favorite to win the pot.
- Is this a violation of the Fundamental Theory of Poker? Yes.
- Is this the optimal play for both players? Yes.
The seeming contradiction comes from the fact that the Fundamental Theory of Poker is a theory which is not about poker. Instead it is a theory about the results of poker. In other words, you cannot use the Fundamental Theorem of Poker to solve any actual poker problems. Instead you can only use it to determine that you were, or were not, unlucky to have been involved in a confrontation where your opponent just happened to be holding a specific hand.