Tactics is knowing what to do when there is something to do. Strategy is knowing what to do when there is nothing to do.
The winner is the one who makes the next-to-last mistake.
To avoid losing a piece, many a person has lost the game
The first essential for an attack is the will to attack.
Psychologically, the choice of an appropriate opening is of the utmost importance for a player's success in a tournament.
As for me, I am unfortunate enough not to posses a happy temperament like Najdorf, who views every happening in a rosy light and avoids any possibility of self-criticism. I am one of those unlucky skeptics who never overlook the dark side of even the happiest experience.