Levels of poker thinking

There are different levels of thinking on which poker players can play.
For example:

Level 1 player thinks about his hand. All beginning players start on this level. Their thought process goes like this: “I have Tc2d, flop is Ts9s8s. I have top pair. Top pair is a good hand, so I’m not going to fold to all this crazy bets and raises”.

Level 2 player thinks about what hand his opponent have. For example: “I cbet two tone flop and got called. Now flush card comes on the turn. My opponent must have hit his flush so I’m not going to put any more money in the pot.”

Level 3 thinks about what his opponent think about his hand. “I raised preflop and cbet flop. Now Ace comes on the turn. If I bet my opponent will put me on AK so this is a good spot to bluff. ”

Level 4 thinks about what his opponent thinking about what he thinks about opponent’s hand. “Scare card comes on the turn and my opponent bets. This is a good spot for him to bluff so I should call him with my 3-rd pair.”

And so on… 

To exploit your opponent’s way of thinking you need to think on exactly one level above him. There is no point in being on level 3 and trying to bluff level 1 thinker – he’s just not going to fold his pair no matter how scary the board is.