Of course, in order to show gratitude to benefactor, I must wish to do the same thing that he must have wished in order to give a benefit to me. Can anything be more unjust than to hate a person who has trodden upon your foot in a crowd, or splashed you, or shoved you where you did not wish to go? Yet, since he actually does us an injury, what besides the fact that he did not know what he was doing exempts him from blame? The same reason keeps this man from having given us a benefit, and that one from having done us an injury; it is the intention that makes both the friend and the enemy. How many have escaped military service because of sickness! Some have escaped from sharing the destruction of their house by being forced by an enemy to appear in court, some have escaped falling into the hands of pirates by having met with shipwreck; yet such happenings do not impose the obligation of a benefit, because chance has no sense of the service rendered, nor does an enemy, whose lawsuit, while it harassed and detained us, saved our lives. Nothing can be a benefit that does not proceed from goodwill, that is not recognized as such by the one who gives it. Someone did me a service without knowing it — I am under no obligation to him. Someone did me a service when he wished to injure me — I will imitate him!