The ties of virtue ought to be closer than the ties of blood, since the good man is closer to another good man by their similarity of morals than the son is to his father by their similarity of face.

Study and research into truth often only serves to make us see by experience our natural ignorance.

Sometimes we praise the way things used to be in order to blame the present, and we esteem what is no longer in order to scorn what is.

Criticism should awaken our attention, not inflame our anger. We should listen to, and not flee from, those who contradict us. Truth should be our cause, no matter in what manner it comes to us.

Everyone is so caught up in his own passions and interests that he always wants to talk about them without getting involved in the passions and interests of those to whom he speaks, although his listeners have the same need for others to listen to and help them.

Self-love makes us deceive ourselves in almost all matters, to censure others, and to blame them for the same faults that we do not correct in ourselves; we do this either because we are unaware of the evil that exists within us, or because we always see our own evil disguised as a good.

Social intercourse, even friendship among most people, is a merely a business arrangement that lasts only so long as there is need.