this is a much better way of explaining a leveled thinking concept i was told once and never really grasped..

level 1 - What do i have?
level 2 - What does my opponent have?
level 3 - What does my opponent think i have? - ISF therom?
level 4 - What does my opponent think i think he has?

Its alot to rap your head around unless you've been..
1. working on reading your opponents alot already
2. working on bluffing as a representation of a given hand rather than just the thought that your opponent doesnt have shit.

putting the 2 together and acting accordingly is the theorem right? and would put you in an immensly powerful position as a poker player. It turns bluffing into a winning play instead of a half hearted hope at glory as it is for most of us when we start.