The second, we'd venture to say, is being able to identify, understand, and fix your mistakes. Fortunately, there are a few elementary (and easily corrected) blunders that nearly all beginner players fall into at some point. Dodge them, and grand mastery -- or, at any rate, a much better standard of play -- is just around the corner.
Here are seven of the most common.
Hands off the queen
Let's be honest about it: queens kick ass. Zooming about the board, owning up the place, they're the chess equivalent of a Sherman tank...except Sherman tanks generally can't be taken out by the puniest of footsoldiers.
Not so your queen. She's a powerful asset, but vulnerable, and you'll hear it from every seasoned chess pro on the planet: one of the most common errors made by beginner players is bringing her out too soon. Resist the urge to run rampant with her majesty.
Avoid pointless exchanges
In economics, there's a concept called the sunk cost fallacy. Basically, it says that once you've lost money on a failed venture, it's gone, and you should think carefully before adding more capital in the hope of getting back your starting stake.
The same applies to lost chess pieces. Is it really worth risking a valuable bishop or knight to get revenge for a taken pawn? Rarely. Don't let your emotions get the better of you. If you lost a piece, let it go and move on.
Chances are you're not playing a timed game. So what's the hurry?
Even if you're confident in your next few moves, take a few minutes to sit back and smell the roses. Have you missed anything crucial? What's your opponent up to? Is there a better play than the course you're currently on? When you rush, you make mistakes. So don't.
Don't pawn off your pawns
The cannon fodder of the chess world, these disposable pieces exist purely to be thrown into a meat grinder of tit-for-tat death in the middle of the board, and if you have any left by turn 15, you're not playing aggressively enough. Right?
Wrong. The pawn might be the least important piece in the game, but that's not the same thing as being unimportant. Acting together with other pieces, pawns are powerful lines of defense, guards, and end-game blockers -- not to mention if you get one to the far end of the board, suddenly you're playing with two queens. Don't underestimate their power, and don't throw them away without good reason.
Castling: not just for Harold and Kumar
Though it's difficult to hand down blanket rules for chess strategy, here's one that comes close: castling, in general, is rarely a bad idea. You get to tuck the king in towards an edge, where he's safer -- and you get to yoink a powerful rook towards the middle of the board, where he's more useful. If in doubt, do it.
If it looks too good to be true...
You know the rest. Your opponent leaves a high-value piece apparently undefended. An opportunity to get one over on him? Maybe.
But before you rush to capitalize on his mistake, think carefully. Could this be a deliberate gambit? Will plucking that tempting prize leave you in a worse position than before? Does your enemy's carefree grin conceal a cunning trap in the works? Only you can answer that -- but there are probably better ways of doing so than putting your head in the lion's mouth.
Avoid tunnel vision
It's easy to concentrate so tightly on one crucial area of the board that you ignore important developments in others. Chess's many fast-moving pieces can appear out of nowhere, and if you're not getting a broad enough view of the action, you risk being caught napping. Work on seeing the whole board.