When I was 10 years old, my father explained me the rules of chess. We used to play once a day and I lost all the time. To motivate his son, he took a banknote – ten Deutsche Mark – and nailed it to the wall over the chimney. He said to me: ‘The first time you win a match against your father, you’ll win the money. But that will take several years.’
We played a match and I lost again. Motivated by the new challenge we played a second round and I earned a draw for the first time. We played again. It was a long, concentrated match and in the end I won against my perplexed father.

Then, I took the banknote off the wall and never played chess again.