Some men, when they have done you a favour, are very ready to reckon up the obligation they have conferred. Others, again, are not so forward in their claims, but yet in their minds consider you their debtor, and well know the value of what they have done. A third sort seem to be unconscious of their service. They are like the vine, which produces its clusters and is satisfied when it has yielded its proper fruit. The horse when he has run his course, the hound when he has followed the track, the bee when it has made its honey, and the man when he has done good to others, make no noisy boast of it, but set out to do the same once more, as the vine in its season produces its new clusters again. Should we, then, be among those who in a manner know not what they do? Assuredly. But this very thing implies intelligence; for it is a property of the unselfish man to perceive that he is acting unselfishly, and, surely, to wish his fellow also to perceive it. True, but if you misapprehend my saying, you will enter the ranks of those of whom I spoke before. They, too, are led astray by specious reasonings. But if you have the will to understand what my principle truly means, fear not that in following it you will neglect the duty of unselfishness.