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There are many reasons why the best chess players may play strange moves. True, sometimes they will play a risky endeavor to get their well-studied opponent out of opening theory. Also, true: sometimes they play unsound lines for the sheer psychology – the “Magician from Riga” Mikhail Tal automatically comes to mind. However, the “most true” reason – or rather most common reason – is that it is simply a good move that we lower rated players have trouble understanding: to them, it isn’t all that strange of a move. This last reason for strange moves is one that we can explore.

Our stem game is a well-known miniature that many chess players, myself included, have memorized. The instructive game I am referring to is from Vienna (Austria) 1910, where Richard Réti has the White pieces and Savielly Tartakower has the Black pieces.

♙ 1. e4 c6 2. d4 d5 3. Nc3 dxe4 4. Nxe4 Nf6 Have you memorized this line so far? A well-versed 1. e4 player should undoubtedly recognize this as the mainline of the famous Caro-Kann Defense. That is the thing about memorizing chess games; it isn’t nearly as difficult as one may imagine, because chess players can recall opening theory and “re-remember” the games they memorized if they understand the principles at play. It is this same skill that allows blitz players to play opening moves correctly as if they were in auto-pilot. If you want to impress your non-chess friends with your chess memorization, then show them a game like this one from memory!

One “move” in chess actually consists of two parts called “ply.” A ply is essentially half of a chess move. 1. e4 is one ply (White’s move) and 1. … c6 is the second ply (Black’s move) of the first chess “move.” This means that to calculate 2 ply deep, is to only look ahead one move (White and Black’s move). In our game, we have passed through move 4 – or 8 ply we had to remember so far. A non-chess friend might think I’ve had to memorize 8 things so far, but I’ve only memorized one single thing! Can you guess? I just think, “Caro-Kann Defense Mainline” and I can replay the moves almost automatically.

♕ 5. Qd3!? Now we encounter a “strange” move. How can we understand why this move was played and how can we easily remember an odd move? Many beginning chess players will become unfairly critical of a move like this because it goes against what they have been taught. One such opening principle that beginners are taught is to not bring out the Queen too early in the game. In many cases, bringing the Queen out early is not favorable, since the Queen can either become trapped, or because the opponent can harass your Queen as they develop with tempo (attacking the Queen while simultaneously developing their own pieces). This strange move breaks that opening principle: it is only move 5 and Richard Réti is already bringing out the Queen: “Oh, what a patzer he is”, many beginners believe. Of course, they themselves wouldn’t play such a move. Another well known opening principle is to keep swift development; do not unnecessarily block lines for your pieces to use for development. This strange move breaks this principle too! The Queen on d3 blocks the path for the Bishop to come out to a square like c4. Rather than believing we can automatically “punish” this strange play, we should consider if it is perhaps something we ourselves are overlooking.

Richard Réti was a strong player and certainly wouldn’t play a move like 5. Qd3 without a reason. We have to recall that Réti was approaching the peak of his chess career. This game was played in 1910 and his peak decade was 1910 to 1920. In fact, 15 years after this game was played: Réti set a world record for blindfold chess. In 1925, he played 29 chess games simultaneously - while blindfolded! Of those, he won 21 games, drew 6 and only lost 2!

This is why I like to call them “Opening Principles” and not “Rules.” “Principles” sounds to me like educated guidelines with exceptions: this is exactly what opening principles are in chess! Too many chess beginners lose their cool at strong players not playing “conventionally”, but it is them missing the point. The strong players become unimaginably strong at chess because they recognize these principles (not rules), yet they are also talented enough to recognize exceptions. If 5. Qd3 in our stem game was one such exception: then how can we understand the meaning behind this move like Réti did over a century ago?

Whenever I am faced with a move I don’t understand, I usually just accept it temporarily and continue playing through the game. Once I have played a few more moves deep, then it is usually apparent to me and I discover what they calculated in their head. I’ll utilize this approach here and we’ll temporarily accept this move as “strange” until we finish the game. Then we can return to the move and see if its meaning has become more apparent.

♟ 5. …e5 If White didn’t play 5. Qd3, then lines like 5. Nxf6 exf6 and either 6. Bc4 or 6. Nf3 appear logical. However, since 5. Qd3 was played: it seems like White is in no hurry to exchange Knights on f6. Since Black doesn’t mind keeping the tension as well, 5. …e5 strikes at the pawn center. 6. dxe5 for White does not win a pawn because Black can always win it back via the Queen fork and check on a5.

♙ 6. dxe5 Qa5+ 7. Bd2 Note that if Black’s check didn’t win back the pawn, then the Queen check might be a dubious move. Black would bring the Queen out unnecessarily early and White would develop a piece (the Bishop) as it attacks the Queen. Opening principles are correct probably 99% of the time, but it pays to be creative and open-minded enough to let yourself discover the rare 1% exceptions without ego getting in the way.

♛ 7. …Qxe5 Tartakower wins back the material, but did White anticipate all of this? Hint: By the end of the game, it is clear that the answer is probably “yes.” Yes, White did anticipate all of this so far and more!

♔ 8. O-O-O Castling Queenside instantly is the only move the engine sees to keep the advantage for White, but it is a nice advantage which we will soon see the idea behind.

♞ 8. …Nxe4?? Does White drop their e4 Knight? Yes, but the double question mark annotation is at least a clue that Black’s …Nxe4 move here is flawed.

♕ 9. Qd8+! White’s Queen sacrifice is the first move of a 3-move mating net.

♚ 9. …Kxd8 forced.

♗ 10. Bg5+ and now this double check wins for White in romantic fashion. Obviously, the previous Queen sacrifice is nothing if the following moves that justify it aren’t correctly calculated.

♚ 10. …Kc7 There is actually some disagreement in detail whether or not this move was actually played in the original 1910 game. Some databases claim that Tartakower resigned upon seeing the double check 10. Bg5+ and other databases claim that 10. …Kc7 was played and met with checkmate. Either way, it is clear that Black is in trouble. The problem is that Black must move their King because both checks can’t be blocked simultaneously. The g5 Bishop attacks the King and so does the unleashed discovered attack from White’s d1 Rook. If 10. …Ke8, then 11. Rd8# follows in resemblance to Paul Morphy’s Opera House Checkmate from his famous 1858 game against Duke Karl and Count Isouard.

♗ 11. Bd8# One reason to believe that Tartakower didn’t resign early is because after 10. …Kc7 11. Bd8# we have the same checkmate pattern that is today known as Réti’s Checkmate – named from this 1910 game in Vienna; I doubt Réti would get a checkmating pattern named after him if the game ended in resignation.

Now that we finished going through the stem game, what was the “strange” idea behind 5. Qd3!? and how can we remember moves we do not understand? The early Queen move to d3 plans castling Queenside quickly from where the d1 Rook will be behind the Queen. This was instrumental in how the stem game played out. Without this early Queen move, there would be no Queen sacrifice: nor would there be a discovered attack for double check. If your opponent plays a “strange” move against you, there could be a list of reasons why: but do not forget to include the possibility that they planned something that you do not yet see. The amazing thing about this 1910 game is that Réti probably calculated all of this out to checkmate before deciding on the mysterious 5. Qd3!? Returning to our original questions, how can we remember moves we do not understand? The answer is by figuring out how to understand them and a good technique to do so is to continue the stem game (or continue to calculate in an ongoing game) and then look back to the move in question. The reasoning will often times become apparent by then.

Furthermore, learning the ideas behind the moves makes replaying a game from memory immensely easier than just remembering move notation with brute force memory. This instructive miniature game is easy enough to remember, because it is only 11 moves long. How can we remember longer games from memory though? We can use the same concept of remembering ideas instead of just memorizing moves: the same goes for remembering opening theory instead of games too! It is much easier if you remember ideas. Let us take this 1910 miniature as an example. Everyone thinks slightly differently, so find whichever memorization method works best for you. However, here is my simple way of memorizing this game. First, I think: “Caro-Kann Defense Mainline.” Then I remember the “strange 5. Qd3 move” White played that characterized this entire game. Next, I remember “Black’s pawn strike in the center” and that virtually automatically plays itself out to 8. O-O-O (another defining move of this game). Finally, I just have to remember “Black blunders by not seeing the mating net via Réti’s mate.” That’s it; instead of memorizing a 21 ply game, I only need to have 5 ideas memorized and I can replay the game from memory. To jog my memory, I just need to think something like: “1. Caro-Kann Defense Mainline 2. Strange Qd3 move 3. Black’s pawn strike in center 4. When Black gains back the pawn O-O-O 5. Blunder into 3-move mating net by Réti’s mate.”

That is how to easily memorize games and openings: remember ideas and not moves alone. This technique of remembering ideas can help you memorize any opening or game; chess isn’t about brute force memorization: it is a game about ideas!