On Clemency, Book I, XVII

No creature is more self-willed, requires more careful management, or ought to be treated with greater indulgence than man.

What, indeed, can be more foolish than that we should blush to show anger against dogs or beasts of burden, and yet wish one man to be most abominably ill-treated by another?

We are not angry with diseases, but apply remedies to them: but this also is a disease of the mind, and requires soothing medicine and a physician who is anything but angry with his patient.

It is the part of a bad physician to despair of effecting a cure: he, to whom the care of all men’s well-being is entrusted, ought to act like a good physician, and not be in a hurry to give up hope or to declare that the symptoms are mortal: he should wrestle with vices, withstand them, reproach some with their distemper, and deceive others by a soothing mode of treatment, because he will cure his patient more quickly and more thoroughly if the medicines which he administers escape his notice: a prince should take care not only of the recovery of his people, but also that their scars should be honourable.

Cruel punishments do a king no honour: for who doubts that he is able to inflict them? but, on the other hand, it does him great honour to restrain his powers, to save many from the wrath of others, and sacrifice no one to his own.