If there is one thing that Poker has taught me over the years, far in excess of life's other experiences, it is that people think in completely different ways. Furthermore, not only are there huge differences between how Player A and Player B think, but more so, how Player A thinks depending on his current state of mind. It is obvious that a player's skill and knowledge contribute to how he will play a hand. Often though, the player's current state of mind can be a greater contribution to how they play a hand. The truly great poker players, will be judging an opponent's current state of mind, and amend the way that they play their opponent accordingly. They will make adjustments to take advantage of how they expect their opponents to play. Here are a few examples of what I mean.
$20 Rebuy NLH Competition with 5 minutes left in the rebuy period.
You raise pre-flop with AK, and you are called by 'MrBigWedge'' in the Big Blind. You have noticed that he has had three or four rebuys, and just had a re-buy the previous hand. The flop is 7,9,10 and the pot size is 600. You have 750 chips left in front of you, but have missed the flop. He has showed a little weakness in checking the flop, and you would love to steal the pot. You shouldn't. It is a flop that provides many draws, your opponent could easily have caught a pair, and he may also fancy his hand if he has underpair. More importantly, the evidence so far shows that he doesn't care if he loses the pot. He may be steaming, or he may just like to play every hand while he can afford to. The best option is to check.
The same $20 NLH completion many hours later.
'MrBigWedge' won the earlier pot against you, and has won several more as well. Just like many good tournament players, he is now a steady player because he has a big stack. Let's presume that you have now both reached the last two tables of the competition. You both have an average stack of 20,000. They are paying 10 spots and there are only twelve players left. You can smell the money.
Lets say you raise 4000 with AK again on MrBigWedge big blind, and he calls. The flop is 7,9,10 again and it looks dangerous. MrBigWedge checks and we have the same scenario, don't we? There is over 8000 chips in the middle that you would love to take down. This time the best option is to make a move on the pot. A bet of 8000, half of your remaining stack, will probably win the pot. Why? All the variables are the same, except that now, MrBigWedge is in an entirely different frame of mind. Now he doesn't want to take risks. He won't want to call on a weak draw, or a weak pair. He will have had to have flopped a very big hand to trap check you here. The pot is probably yours for the taking.
You may think that the above scenarios are extreme scenarios. They may be a little so, but the next time you play, watch players betting patterns, and see how they can change. The most obvious and consistent changes that I see when playing competitions are after a player has just been involved in a pot. I am sure we have all seen a play go on tilt after losing a big pot, regardless of whether he is unlucky or not. All of his sudden he will be playing with any two cards. The important point though, is to know how to take advantage. A player on tilt, doesn't care. You cannot bluff him, so don't try. If you have a real hand though, fill your boots.
Conversely, if a player has just won a big pot, he is often affected the opposite way. How often have you been dealt a marginal hand, straight after scooping a big pot, and your instinct is to just throw it away. You don't want to get involved and risk losing the chips that you have just won. This is the most usual reaction. It follows that a player in this state of mind, can be bluffed more easily. Don't expect to get paid off when you have a good hand though.
Winning or losing a pot is not the only influence opponents play though. Rebuy periods, getting close to the money. I have seen players upset by something that has been said in the internet chat box. In live play I have seen players affected by a waitress forgetting their coffee. Unfortunately, with the internet you may not be able to see many things that may affect an opponents play: a Patriots turnover, a phone call, interference from the wife or even a bad beat whilst playing on another table at the same time. This is one of the great differences with live play. You can see your opponents and judge their state of mind.
To summarise though. Poker isn't just about cards. Poker tournaments aren't just about cards and chips. There is a third variable: 'Psychology'. This is what often separates the men from the boys, the brilliant from the good, the Winners from the Losers.