Through zeal knowledge is gotten, through lack of zeal knowledge is lost; let a man who knows this double path of gain and loss thus place himself that knowledge may grow.
Moderation, which consists in an indifference about little things, and in a prudent and well-proportioned zeal about things of importance, can proceed from nothing but true knowledge, which has its foundation in self-acquaintance.
At least two thirds of our miseries spring from human stupidity, human malice and those great motivators and justifiers of malice and stupidity, idealism, dogmatism and proselytizing zeal on behalf of religious or political idols.
There is not a vice which more effectually contracts and deadens the feelings, which more completely makes a man’s affections center in himself, and excludes all others from partaking in them, than the desire of accumulating possessions. When the desire has once gotten hold of the heart, it shuts out all other considerations, but such as may promote its views. In its zeal for the attainment of its end, it is not delicate in the choice of means. As it closes the heart, so also it clouds the understanding. It cannot discern between right and wrong; it takes evil for good, and good for evil; it calls darkness light, and light darkness. Beware, then, of the beginning of covetousness, for you know not where it will end.