Emanuel Lasker

He who wants to educate himself in chess must evade what is dead in chess... the habit of playing with inferior opponents; the custom of avoiding difficult tasks; the weakness of uncritically taking over variations or rules discovered by others; the vanity which is self-sufficient; the incapacity for admitting mistakes; in brief, everything that leads to standstill or to anarchy

By some ardent enthusiasts Chess has been elevated into a science or an art. It is neither; but its principle characteristic seems to be what human nature mostly delights in-a fight. Not a fight, indeed, such as would tickle the nerves of coarser natures, where blood flows and the blows delivered leave their visible traces on the bodies of the combatants, but a fight in which the scientific, the artistic, the purely intellectual element holds undivided sway

The outcome of a move is often uncertain because we cannot take all possibilities into consideration. Man is too frail. Life is too short for such a task. Therefore, we have often to be content with the commonsense procedure of strengthening our force so as to be ready to meet unforeseen emergencies, but in positions which we can completely analyze we should attempt to arrive at deductions because analysis is definite and convincing, and in that respect superior to commonsense

You should keep in mind no names, nor numbers, nor isolated incidents, not even results, but only methods. The method produces numerous results; a few of these will remain in our memory, and as long as they remain few, they are useful to illustrate and to keep alive the rules which order a thousand results

The laws of chess do not permit a free choice: you have to move whether you like it or not