As we said then, generally speaking, we should repay what we owe: but if giving [instead of repaying] be more noble or meet a more pressing need, it is right to incline in this direction; for sometimes it is not even fair to repay the original service, e.g. when one man has helped another, knowing him to be a good man, while the latter in repaying him would be helping one whom he believes to be a bad man. And so a man is sometimes not bound to lend in turn to one who has lent him money: A may have lent to B in full expectation of being repaid, as B is an honourable man; but B may have no hope of being repaid by A, who is a rascal. If this be the real state of the case, the demand for a loan in return is not fair; but even if the facts be otherwise, yet, if they think thus of each other, their conduct would be regarded as natural.

As we have often said, statements concerning human affections and actions must share the indefiniteness of their subject.