In such cases, then, we should, if we have the power, make an equivalent return for benefits received (for we must not treat a man as a friend if he does not wish it: we should consider that we made a mistake at the beginning, and received a benefit from a person from whom we ought not to have accepted it⁠—for he was not a friend and did not act disinterestedly⁠—and so we ought to terminate the relation in the same way as if we had received a service for a stipulated consideration): and the return should be what we would have agreed 229 to repay if able; if we were unable, the donor would not even have expected repayment. So we may fairly say that we should repay if we have the power.

But we ought at the outset carefully to consider who it is that is doing us a service, and on what understanding, so that we may accept it on that understanding or else reject it.