The fundamental theorem of poker
First I should admit that I’m not pretending to be the author of this idea. But the experience I have for the moment confirms that it’s true. It could bring you the money if you follow it and rob you if not.
I’m speaking about The Fundamental Theorem of Poker. Every guy who’s going to play poker should understand this concept. If you are playing more often than once a month you’ll feel the difference.
And your family also will feel the difference (^_^)
The statement of The Fundamental Theorem of Poker is very simple to understand. But it’s much more difficult to imply to your everyday poker as it demands much from you.
It says:
“If you could play the hand better knowing the cards of your opponent than you were mistaken and that hand has brought you losses. This is true even if you had won the hand. On the other hand if you couldn’t play better knowing the cards of you opponents than you are earning the money even on the case loosing a hand”.
This seems a little bit difficult to understand but it becomes much clearer in these examples.
Consider you have 
and your only opponent has 
.
Preflop
You are on BB and he is on SB. He completes to BB and you are checking.
The flop brings 
.
He bets and you call.
Turn and 
.
He bets and you call.
River 
.
He checks and you check too.
As a result you are winning 4 Big Bets with your higher pair earning 2 Big Bets. But if you know the hand of your opponent you were playing differently.
First of all you’d better raise on preflop as your hand is much better than your opponent’s one. This would probably bring you one more bet or an opportunity to win the money without the risk of loosing 277 deck. Then you’d better raise on flop and turn and bet on river for the same reasons. As a result if your opponent call you to showdown you could win 3 more Big Bets from this hand. Frankly speaking you’ve lost these 3 Big bets in this hand.
Got it?
The other situation. Again you are playing heads up with one guy. And again you have and your only opponent has .
Preflop.
He completes SB to BB and you are raising. He calls.
The flop brings .
He checks, you bet and he calls.
Turn and .
He checks, you bet and he calls.
River 
.
He bets and you fold!
On the first glance seems that you’ve lost a lot of your money in vain. But let’s consider your play if you know the cards of your opponent.
Preflop. You have much better cards that will bring you money against your opponent’s hand in most cases. So in most cases you will win the money he put to the pot.
Flop. You have an overpair. You have a pair of aces. It’s like the situation that you have pocket aces that didn’t match the deck. What do you usually do with pocket aces? You bet for sure! And you know that the only cards that could help your opponent are sevens and twos. So there are only 5 cards that could help your opponent and 42 that brings the money to you… Is it enough advantage to bet? I think yes. So again your bet is the best decision you could do.
Turn.
Nothing have changed. Again you have a huge advantage that drives you to bet. Your probability to win had even grew as there is only one opportunity left to change the situation (if you know basics of probability theory you could calculate the proofs for that statement).
River.
Oops! Seems he got the card that improved him over us. In real poker you don’t fold usually in such situations as there could be bluffing. But if we know the cards of your opponent you should fold for sure.
So as a result you have lost this hand. But in more than 80% of such hands you will win. You haven’t given you opponent any additional opportunity to increase his gains. And the next time you’ll win more.
You should clap the guy on the back and cheer him as WSOP winner. He will pay you in the next several minutes.
So it’s very important for a poker player to read the hands of his opponents and to behave himself accordingly.