[Jeff76]

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I read in TOP (chapters 2 & 3) that profit comes from having an advantage over your opponents. In other words, you earn a profit when an opponent makes a "mistake".

[/ QUOTE ]You must keep in mind what "mistake" means in this case. For instance, say you are playing NL holdem, are in the BB with 10 BBs, get dealt KK, and everyone folds to the SB who pushes all in. Folding would be a clear error, but if the SB were holding AA, then you have made a "mistake" according to the FTOP.

Everyone makes these "mistakes". Good players make less of them and generally lose less money when they make them.

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At the lower levels, "mistakes" are frequent and blatant. People will cold call raises with A6o or K7s.

[/ QUOTE ]If you are playing deep stack NL, some of these "mistakes" might not be as bad as you think. Often they are because the players aren't good enough to play these hands, but these "mistakes" might be small enough in good players hands that they can make up for them by inducing bigger mistakes from their opponents later in the hand.

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Obviously, a basic understanding of the game allows me to be profitable at this level, but I am completely confused how to play at a higher level.

[/ QUOTE ]Like all poker, they do it by inducing more costly errors in their opponents play than they themselves make. Playing "reasonably sound" is not going to do it in a game of experts, because they are manipulating you into folding hands you shouldn't and playing hands you should fold.

Think about this. Say you get dealt AA in UTG (NL HE) and you go in for a standard raise. And say a player better than you on the button knows that you'll only raise UTG with a few select hands. You are basically playing with your cards fac up. In this case, what can he call you with profitably? Just about any two cards, really. If he knows you can fold an overpair then he can outplay you. And if knows that you'll never fold, his implied odds are huge. So now you have to start opening your range so that it isn't obvious what you are holding, but then your playing out of position with a weak holding against players better than you. But what else can you do? Fold aces? Of course not- you're just in over your head.

Poker is never straightfoward or a matter of just making standard textbook plays, and the higher you get the more this is true. This isn't just ture of NL HE, but it's the easy place to find examples. I can't beat levels where people outplay me like I've outline above. But I can play fairly standard poker and beat the softer games, so that's where I play- for now at least. I am learning "moves" as I go, and these "moves" often are only good at certain levels. At the lowest levels of poker, almost any move other than drawing the nuts is worthless, but a little higher and some plays start working better. Once again, by inducing my opponents to make "mistakes".

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Is there another level that I simply don't understand yet? In other words, where do profits come from when you are playing against other good players?

[/ QUOTE ]The profit always comes from the fish- and except for a very few select players, everyone is a fish in someone's game. The trick is to find a game in which you're not a fish and learn the moves to make you not-a-fish when you move up.