Kasparov, Donner and the infinite regress of knowing
Last week, in an important team match, my opponent played an innocent sideline against my pet-opening. I had prepared quite well for this encounter, but had not looked at this particular variation since it is so rarely played. Over the board, I knew I had once looked at this line in detail, and had also found a nice way of dealing with it - but to my chagrin I couldn't remember it now. Slighly altered version of the Homunculus Objection adapted by Dave Cantrell, originally published in Smithsonian 16 (1) (April 1985):97.For some minutes I tried to retrieve the lost knowledge from the depths of my memory, but to no avail, so I decided to be practical and play a natural move instead. Further on in the game, in a normal middlegame position, instead of just playing some natural move, I suddenly saw a funny little intermediate move, weakening my kingside but weirdly complicating the position. I briefly started calculating the consequences of the move and I started to like it more and more. After some time, since I couldn't find a clear refutation, I played it.The funny thing is that all the time while I was contemplating this crazy little move, I was totally aware of its 'ugliness', of how utterly 'unnatural' it looked and how unpositional its foundations really were. Despite this, I decided it was worth the risk and offered interesting fighting changes. Unfortunately, it turned out the move was rather easily refuted and I was left with a wrecked kingside, resulting in a zero for the team. (Though we did win the match.)These situations are examples of a phenomenon called metacognition, or 'knowing about knowing': I knew I knew a particular opening line, but I just couldn't remember it. Likewise, in the middlegame, I knew my weird idea was against all positional rules, but I played it anyway.A famous chess-related anecdote involving metacognition was once described by Tim Krabbé is his story A Walk with Kasparov. In this story, Krabbé describes how Garry Kasparov, having just lost to Jeroen Piket in the last round of the VSB tournament in Amsterdam, starts talking to him after the game. Kasparov tells Krabbé he had prepared the novelty he played in the game, but then to his horror couldn't remember the lines:
I ask him: 'Do you mean to say that Re4 might be in your computer and you forgot about it?' 'Maybe, maybe,' he says. 'I'm just curious to know. Are you curious too?' 'Yes I am.' 'Then come to my hotel and we'll check.'Krabbé joins him and Yuri Dokhoian to Kasparov's hotel room, and watches as Kasparov opens his laptop, expecting to find the idea behind the novelty 19...Re4 hidden in his database. But even now, Kasparov can't find his forgotten home preparation, which Piket refuted with the reply 20.Bg3!
He is desolated, but he cannot find 19.Na4, let alone 19...Re4. He's absolutely sure Na4 is in one of his computers somewhere, but it doesn't seem to be in this one.

Garry Kasparov in September 2009 in Valencia
What's interesting about this mental hiccup is that, even though the mind can't remember the information, it's convinced that it knows it, which is why we devote so many mental resources to trying to recover the missing word. (...) But here's the mystery: If we've forgotten a person's name, then why are we so convinced that we remember it? What does it mean to know something without being able to access it?The larger question is how the mind decides what to think about. After all, if we really don't know the name - it's nowhere inside our head - then it's a waste of time trying to find it. This is where metacognition, or thinking about thinking, comes in handy. At any given moment, we automatically monitor the flux of thoughts, emotions and errata flowing in the stream of consciousness. As a result, when a name goes missing we immediately analyze the likelihood of being able to remember it. Do we know the first letter of the name? Can we remember other facts about the person? Are we able to remember the first names of other acquaintances from high school? Based on the answer to these questions, we can then make an informed guess about whether or not it's worth trying to retrieve the misplaced memory.The interesting thing in the Kasparov example is, in my view, that Kasparov did not remember correctly. As said, he was sure of something he shouldn't have been sure about. He was too confident of himself, perhaps: after all, someone like Kasparov has to remember such an awful lot of variations that inevitably, something goes wrong in his head from time to time. Maybe he would have been helped by something Jonathan Rowson describes in his book Chess for Zebras (2005): unlearning. Say what?
Basically, according to Rowson, Kasparov should have looked at the position after 19.Na4 with 'fresh eyes' and realized that even if he had once analysed 19...Re4, he didn't like it after 20.Bg3. He should have unlearned what he thought he had learned, so to say. He should have ignored the voice in his head telling him to play the 'analyzed' move Re4.But wait a minute ... does ignoring the voice in your head also imply that in my own above mentioned game, I was actually right in playing that ugly-looking move', ignoring my intuition and going for concrete, 'fresh' complications? Stubbornly, consciously going against your intuition and your natural sense of reality was often subject of the chess writings of J.H. Donner. Here's how he described his thoughts during a game against Milic in 1950:Unlearning is really a way of of constantly looking at the baggage you bring to chess positions ans trying to work on the baggage that is most obviously problematic. It is also a way of trying to look at chess positions with fresh eyes, as free as possible from prejudices. When you succceed in doing this, you start to see the prejudices as prejudices, and not as absolute truths, and that's when real improvement becomes easier.Jonathan Rowson in November 2008 at the Dresden Olympiad
Until this moment I hadn't used much time to think, just fifteen minutes on my 19th move. Everything went fine, I saw everything and felt contempt for my opponent. But now a paralysing doubt overwhelmed me. Suddenly, I saw white pieces coming from all sides, while I was clearly aware that White didn't have a realistic chance. 'Stay calm,' I said to myself. 'You're winning.' But it didn't help. I couldn't calm down. I did see the best move in the position, h5, and I wanted to play it, but I touched my rook and played Rg8.

J.H. Donner (6/7/1927 - 27/11/1988)
Two souls, alas, are housed within my breast, and each will wrestle for the mastery there.If you don't recognize this feeling, make sure you'll forget this article right away - before it's too late.
