You can’t calculate what you can’t see

I was playing online blitz early in the morning this week when my opponent fell into a well known mating trap on move 8.  The mating pattern is very pretty and always satisfying but it also occurred to me that it appeared to be one of those positions that everyone seems to fall into.  Bemused at why this would be the case I decided to look at some statistics and noticed that despite being a relatively rare line, every time I had had the position my opponent had walked into the trap.  I’ve talked about the difference between amateur and professional players before and this sequence is another lovely example.

The line in question stems from the Chigorin Defence of the Queens Gambit Declined.  After 7…Nxe5 it first appears that black is losing a knight.  However, it doesn’t take too much calculation to spot the checkmate threat on d1 should white decide to snaffle the knight on e5.

Indeed after white allows 7…Nxe5, black has equalised and discretion is the better part of valour for white with recommended moves such as Be2 or Nbd2.  However, in the four times I have had this position arise in my games, all four times I have delivered checkmate on d1 on move 8.  Now we can argue that these games are online and amongst amateur players but I do find it fascinating the confidence with which the black knight is snaffled on e5.  Sometimes the white player plays the mistake instantly, sometimes they think for a long while and still play the move. Why is this?

It is a common mantra amongst chess professionals and coaches that good players know when to start burning time in complex calculation.  Knowing when to invest time is a key skill. However, as well as knowing when to spend time calculating you also have to know what to calculate.  If you don’t see a threat or are blind to its existence then you will not calculate and obviously miss the risk resulting in losing to checkmate on move 8. The position in our line we are analysing, I believe, is a very good example of a position that the amateur mind struggles with.  There are a number of factors at play in the position, one or all of which could contribute to this very common mistake.  Lets list them out:

  • A queen less early middle game – Only two pieces are developed by either side and the queens have left the board.  Why would white necessarily be on the look out for mating threats against his own king?  Indeed, he or she has to calculate the knight capture doesn’t lose material (and it doesn’t) but an actual mate threat is not on whites radar;
  • The threat only arises from a vacated square – The checkmate is only possible by white releasing the power of the bishop onto d1 by vacating f3. Threats occurring by vacating squares are intrinsically harder to visualise when calculating;
  • The knight capture wins material – Whats not to like about winning material?! Greed is a powerful bias;
  • Its easy for white to believe black blundered – Until a move earlier the knight on f3 was pinned.  Following the exchange of queens this is no longer the case but it is easy to see how white would think black had miscalculated and blundered by grabbing the e5 pawn by telling themselves that black thought the f3 knight was pinned;
  • The capture on e5 creates nice threats on blacks king – As well as all of the above points, the white pieces start to build a lovely threat on f7 against blacks king.  Its easy to see how white could spend time calculating future threats and attacking options while simultaneously missing threats against his own king.

Having read the above list now lets look at the position side by side with the board flipped. Try looking at each board position and then running through the kind of thought process that white would be walking through.  I don’t know about you, but I actually think the threat is harder to see from the white side of the board because the position for white seems so appealing.

The same position from both white and blacks perspective.  Hard to believe that a mate in 1 threat exists and how the board can appear  so different from either side.

To be fair, I don’t know how many of the above factors contribute to the blunder 8. Nxe5 but it is highly likely some of them play a significant role (NB – Not a lot of people know that I am professionally trained in the analysis and evaluation of human error in complex environments.  A story for another time…).

Here we have a tempting position for white with many positive features such as material gain and kingside attacks combining with a very subtle, hard to see, totally unexpected terminal threat. A nasty combination for the amateur chess player to comprehend which seems to be the chess equivalent of all that glitters is not gold and bring me nicely to the title of this blog post.

You can’t calculate what you can’t see.

In our example, the amateur white player can calculate for as long as he or she likes but if they do not recognise the danger of checkmate then they will simply run analysis on the safety of their developed pieces and the opportunities for future attacks. Many stronger rated players could often laugh and scoff at such a blunder as 8.Nxe5 but I believe this would be unfair.  Human chess players (amateur and professional alike) are not computers. They do not calculate everything.  They only choose to calculate what stories they tell themselves.

“She’s just blundered that knight.  Surely she cannot take my pawn on e5?”

“If I take it then f7 looks weak”

“Queens are off.  There are no real threats at the moment.  I don’t see how he is gaining the piece back it must be a blunder”

“My f3 knight is no longer pinned!”

If your internal dialogue is spinning stories with a different narrative to the reality of the position on the board then the amateur player is in trouble.   In my games 100% of amateur players blundered and walked into checkmate on move 8.  Of the 9 Master Games in the database I looked at 0% of professionals did. Indeed the skill set  to remain completely objective when looking at any position is likely one of the key defining characteristics of weak vs. strong players.

I just loved this example as it seems to fall into that rare category of positions that really seems to befuddle the amateur mind.

Until next time…


mecircle

Jon Fisher

Jon is the Editor of The Bristol Chess Times and Publicity and Recruitment Officer for The Bristol & District Chess League. He plays for Horfield Chess Club and has been known to play 1. b3 on occasion.

 

 

 

 

 

 

Book Review #1 – 100 Chess Master Trade Secrets by Andrew Soltis

“100 Chess Master Trade Secrets: From Sacrifices to Endgames” (Batsford Chess) has been on my book shelf a while and is a book that I regularly dip back into, especially before big tournaments.  Ive always been a massive fan of the writing of GM Andrew Soltis, so who better to start with for the first official book review on the Bristol Chess Times? Lets take a closer look…

Screen Shot 2018-02-24 at 13.03.59

I love the design of the Batsford Chess book covers

What is a Priyome? Pardon? Even the most ardent chess players may not have heard this expression before!  GM Soltis explains at the start of the book that a Priyome is a Russian word which is best translated as a strategic pattern or a theme that a player can learn and apply in many situations. He talks about how the Soviet Chess School believed that there were a set of top Priyomes that every master has to learn in order to progress.  For example, in the diagram below, a simple priyome in a pawn and rook endgame with a single open file would be 1. Rd1 and 2. Rd7 leading to advantage white.

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Priyomes and other strategic motifs are effectively the top trade secrets referred to in the title of the book.  GM Soltis believes that the 100 trade secrets described in the book are all known by masters and therefore essential for an ambitious amateur to learn. The book is effectively split into four chapters, each containing 25 examples of the patterns across four key categories:

  • 25 Key Priyomes
  • 25 Must-Know Endgame Techniques
  • 25 Crucial Sacrifices
  • 25 Exact Endings

Each trade secret has no more than a handful of pages dedicated to it in order keep each particular lesson light and simple, something that I enjoy and find easily accessible.  An essential need for the time poor club player with a busy life.  This choice of light touch lessons also has another advantage.  You don’t have to read the book in any particular order, or for any great length of time.  It reads more like a reference book that you can dip in and out of.  For example, with a big tournament coming up perhaps I will just refresh my memory on the top 25 priyomes (remember this means strategic device) to aid my planning and thinking.  Perhaps I will only feel the need to dive into five of these. Perhaps I will just remind myself of which openings in the Crucial Sacrifices chapters involve sacking the exchange on f3.

The great thing about this arrangement in the book is that I suspect most players pick up 100 Chess Master Trade Secrets and know a reasonable percentage of the content already. This leaves the reader reassured in their personal chess ability but also encouraged that they are also plugging valuable gaps to make them a better all round player.

To give you an example of trade secret that I suspect most club level players rarely think of (atleast below 1800 ELO), here is Crucial Sacrifice #5:The File Plugger

The File Plugger

GM Soltis writes:

This arises in several different pawn structures with an open file.  The sacrificer, White or Black, wants to close the file and secure positional benefits like a protected passed pawn.

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Epishin – Dolmatov. Russian Team Championship 1992. White to play

White can occupy c7 with his rook but it can be challenged by …Rc8.

Better is 1. Rc6! threatening the pawns on b6 and d6.  After the forced 1…Bxc6 2. dxc6 we can evaluate:

a) White created a protected passed pawn at c6.

b) He opened a splendid diagonal leading to f7 and threatens Bc4

c) He is virtually certain to win back atleast one pawn.

Of course, Black has an extra exchange. But rooks need files to prove they are superior to minor pieces. Since the c-file is now plugged up, a diagonal, a2-g8 counts much more. 

(p129-130 in 100 Chess Master Trade Secrets, Batsford Chess)

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The completed File Plugger

The author goes on to explore the idea of the “File Plugger” in more detail over the next handful of pages but again not to the extent of covering all known theory.  His intent is to provide the reader with a memorable principle (the names he chooses also help in this regard) that can be taken forward into your amateur games and hopefully spark an idea at the right time over the board.

Conclusion

In conclusion, I can thoroughly recommend this book to the amateur club player as I feel it just has so much to practically offer. For very experienced players I believe it still provides value as even if a player already knows 80 of GM Soltis’s 100 trade secrets, how much of a difference to their game could the remaining 20 make?  The structure of the book aids easy study, allowing the club player to focus on a number of key areas, specifically strategic themes, sacrifices, and endgame techniques without overwhelming the reader (like a lot of endgame manuals and tomes do).

Overall, a refreshingly different approach to learning key principles.

Here is a link to 100 Chess Master Trade Secrets.

Finally, I’ve been planning to write some book and DVD reviews for the Bristol Chess Times for a while now. If you are a regular reader and want to get involved in telling us about a particular favourite book or DVD then do get in touch at bristolchesstimes@gmail.com.  We always welcome contributions from new authors.


mecircle

Jon Fisher

Jon is the Editor of The Bristol Chess Times and Publicity and Recruitment Officer for The Bristol & District Chess League. He plays for Horfield Chess Club and has been known to play 1. b3 on occasion.