②People who are to be happy fix their attention on the convenience of things: the pleasant parts of conversation, the well-prepared dishes, the goodness of the wine and the fine weather. They enjoy all the cheerful things. Those who are to be unhappy think and speak only of the opposite things. Therefore, they are continually dissatisfied. By their remarks, they sour (使变坏) the pleasure of society, offend(顶撞) many people, and make themselves disagreeable everywhere. If this turn of mind was founded in nature, such unhappy persons would be the more to be pitied. The intention of criticizing(批评) and being disliked is perhaps taken up by imitation(模仿). It grows into a habit, unknown to its possessors. The habit may be strong, but it may be cured when those who have realized its bad effects on their interests and tastes. I hope this little warning may be of service to them, and help them change this habit.

The phrase“ sour the pleasure of society” most nearly means“（）”.