[jeffnc]

[ QUOTE ]
In chess, there is absolutely no "hidden" or "unknown" information. Everything that is true, or can possibly become true, is able to be determined by either or both players based on what is visible on the board. Sure, one player might trick another one into thinking that the will do one thing and then do another, but that possibility can always be surmised by a true master.

[/ QUOTE ]

This "complete information" idea is commonly bandied about. It's true in theory, but not in practice, at least among amateur players.

It's true that while playing a "true master" you won't be able to get away with anything, against opponents at your own strength (less than master), chess is really not a game of complete information in practice. You have to pick up on your opponents strengths and weaknesses. You can pick lines he's not familiar with. Not everyone has the abilitiy to recognize all the information available to him. Some players are better at book lines, some are better at strategy, some are better at tactics. Some are better with positional analysis, some are better at sharp, open games. Some are better getting to an endgame safely where they can leverage their advantage in king and pawn play, while others are better at earlier fireworks.

It certainly is possible to bluff in chess (as you said not against a "true master".) But practically speaking, different information is available to the 2 different opponents.

To make an analogy, you could have the equivalent of a 1500 chess rating and make a lot of money at poker. That rating will certainly not make you any money at chess, even though you can win most of your games :-)