What are the chess principles that you rely on most?

What are the chess principles you rely on most? Or, alternatively, what concepts did you learn that are most critical to your progress? The terms principles and concepts are used loosely here, feel free to include any idea, guideline, rules of thumb and/or dogma.

For me the principle that remains most relevant is to always try to identify what are the most forcing moves by looking for checks, captures and attacks. I don't apply this check deliberately every single move, but more often than not I'll use it subconsciously and because of it I blunder less than I did before.

The biggest eye-opener for me was probably learning the idea that it's better to let your opponent take your pieces than to take theirs (assuming no pieces are hanging). That might be one of the biggest changes in the way I play chess. This came with the advantage that I was no longer losing control of open files, simply because I traded Rooks. The biggest difference was that it changed the type of positions I was playing. Especially when I stopped automatically trading pawns in the center, but instead kept the tension. A whole new world opened up to me.

Anyway, these are mine. I'd love to learn what are yours.

• Control the center
• Develop pieces quickly
• Castle early
• Rooks belong on open files
• Two minor pieces are worth more than a rook and pawn
• Three pieces is a mate
• Never play f6
• Work out your opponent's best next move, and don't let him play it

For me, it’s about staying on tempo, piece activity and exerting positional pressure in the middle games.

Decent list, but some of these are also not true. For example, there are many times where ...f6 is the best move (You know it too GM Ben Finegold xD). However, this is a good guideline because you typically don't want to be moving pawns in front of your castled King.

Similarly, "Three pieces is a mate" isn't necessarily enough. Checkmate usually happens if the attacking side has at least 2 more attackers than defenders. If the attacking side has 3 pieces, but the defending side has 2 pieces, then checkmate might not be forcible.

The top 3 in this list I stand by strongly though. Those are the three most important opening principles in my mind. Develop pieces, control the center and castle early are the three most important in my opinion; maybe even in that order.

Isolated pawns are bad. Prefer not to double your own pawns unless you can create structure with them which is difficult to attack. Passed pawns are good if you can defend them. An active piece is more valuable than an inactive piece. Take extra care when your King is one move from any Check.

Another fundamental I really try to adhere to comes from Yasser Seirawan:
Between trying to force some brilliant tactical play or just trading off into an easy boring endgame win, I'll take the easy endgame every time.

Good guidelines to follow. Not to play devil's advocate here, but there are times where isolated pawns, or doubled pawns, can actually be a good asset - not a weakness! It is just that from a pawn structure perspective (and especially if everything trades into a pawn endgame), usually isolated pawns and doubled pawns are a weakness.

Play an open game and trade off into the end game when significantly behind on time. Lock pawn structures and reject trades when significantly ahead on time.

never play the polish opening

Yes! I love endgames and Seirawan is such a good personality

Just be careful about trying to simplify into an endgame too much. Years ago, I used to simplify into winning endgames too much because I would take it to the extreme of giving up part of my slight advantage just to reach an endgame I thought I could win. This was harmful for my long-term improvement because most of the time, I WOULD win those endgames. This was harmful because then I didn't notice the problem. The problem with trading into those endgames is that sometimes you can keep more pressure on the opponent by not trading, so it should be a judgement call whether to trade into an endgame, or to keep some attacking pressure on the board.

Here is a video I made a while ago on this danger which held me back for a long time:

Develop pieces early. My two additions to that are 1) Knights before Bishops and 2) Keep developing pieces.

Two minor pieces > Rook and pawn. Good one, that helped me as well.

Three pieces is mate. I use two more attacking pieces as my guideline.

Never play f6. I've considered that one as more of a meme than as serious advice, but I could be wrong.

@Chuck639, good ones.

@KeSetoKaiba #6 Great. So top 3 is Develop pieces, control the center and castle early.

@CraigIreland #7 all good. The one I like most: An active piece is more valuable than an inactive piece.

@FullTiltBunny. Sound reasonable. Something I should work on, because I'd probably pick tactical play over boring end games every single time.

What do you mean? Is the idea that end games are easier to play with little time left? Conversely, rejecting trades and keeping the position locked will benefit the player that has the most time left to calculate the implications of a position?

A player who is significantly behind on time needs to bring the game to a conclusion to avoiding timing out. It takes less clock time to do that when the game is open. Unless you can already see a reliable way to win the game in midgame it will almost always be faster to conclude with an endgame.

Yup - good post. Let me just add some information to that

Knights before Bishops I don't really like as an opening principle (one of the opening principles I actually don't like that much). I think it is only indirectly true most of the time. I'll include a video where I elaborate the more "advanced" way of thinking about priority of piece development (where a piece "belongs" and is optimally placed).

Two minor pieces better than a Rook and a pawn. Yes, I agree. This one is usually true; this is especially true in the opening and middlegame when the two pieces you gave up were probably active and the opponent remaining Rook is more likely to still be undeveloped. I am reminded of the words of IM Jeremy Silman: a Rook (and a pawn) is just one piece, but "two pieces is a gang."

Again, we agree Two more attackers than defenders usually is enough to force checkmate. This is attacking principle I first learned from Kasparov. I'll include that video concept too.

Lastly, the "never play ...f6" is almost like a meme, but GM Ben Finegold has some real truth behind it. It isn't that you should "never" more your f-pawn. It is just that there are very real and very permanent positional weaknesses when you advance pawns and this is especially dangerous in front of your castled King. Here I'll include a video I made for beginners on why advancing pawns in front of your castled King is generally weakening.

I'd go further than that. Advancing the f-pawn, before castling, for either player, is usually a bad move. That's f3, f4, f5 and f6.