Above all else, before playing in competitions a player must have regard to his health, for if he is suffering from ill-health he cannot hope for success. In this connection the best of all tonics is 15 to 20 days in the fresh air, in the country.
Mikhail BotvinnikMemorization of variations could be even worse than playing in a tournament without looking in the books at all.
Mikhail BotvinnikCapablanca's phenomenal move-searching algorithm in those early years, when he possessed a wonderful ability for calculating variations very rapidly, made him invincible.
Mikhail Botvinnik