31．学会趋利避害

学会趋利避害。霉运往往是对愚蠢的惩罚，且极易传染。不要以恶小而开门，因为大恶往往会随之而来。玩牌的诀窍是：你应明白自己何时该舍弃某张牌。在过去的一局中，最大的牌也比不上现在最小的王牌。假如你举棋不定，记得结交智慧而审慎的人，他们迟早会赢。

31．Select the lucky and avoid the unlucky

Select the lucky and avoid the unlucky. Ill-luck is generally the penalty of folly, and there is no disease so contagious to those who share in it. Never open the door to a lesser evil, for other and greater ones invariably slink in after it. The greatest skill at cards is to know when to discard; the smallest of current trumps is worth more than the ace of trumps of the last game. When in doubt, follow the suit of the wise and prudent; sooner or later they will win the odd trick.