We need not regard what good a friend has done us, but only his desire to do us good.

Self-love is even deceived by self-love, because by looking out for our own interests and disregarding those of other people, we lose the advantage that comes with the exchange of favors.

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.

In knowledge of human affairs, we should never allow our minds to be enslaved by others by subjecting ourselves to their whims. We must maintain freedom of thought, and never accept anything of purely human authority into our heads. When we are presented with a diversity of opinions, we must choose, if we can; if we cannot, we must remain in doubt.

Often the desire to appear competent impedes our ability to become competent, because we more anxious to display our knowledge than to learn what we do not know.

It is a very trying task for deceitful people, always to have to cover up their lack of sincerity and to repair the breaking of their word.

Although we should not love our friends for the good that they do us, it is a sign that they do not love us much if they do not do us good when they have the power to do so.