In his words he is “chaotic and lazy”.  It’s hard to imagine the number one chess player in the world as such.  Fascinating interview:

SPIEGEL: Mr Carlsen, what is your IQ?

Carlsen: I have no idea. I wouldn’t want to know it anyway. It might turn out to be a nasty surprise.

SPIEGEL: Why? You are 19 years old and ranked the number one chess player in the world. You must be incredibly clever.

Carlsen: And that’s precisely what would be terrible. Of course it is important for a chess player to be able to concentrate well, but being too intelligent can also be a burden. It can get in your way. I am convinced that the reason the Englishman John Nunn never became world champion is that he is too clever for that.

SPIEGEL: How that?

Carlsen: At the age of 15, Nunn started studying mathematics in Oxford; he was the youngest student in the last 500 years, and at 23 he did a PhD in algebraic topology. He has so incredibly much in his head. Simply too much. His enormous powers of understanding and his constant thirst for knowledge distracted him from chess.

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