A similar natural inducement has led men to realize that they have as much duty to love others as to love themselves. Things that are equal must be measured by a single standard; so if I inevitably want to receive some good— indeed as much good from every man as any man can want for himsel—how could I expect to have any part of my desire satisfied if I am not careful to satisfy the similar desires that other men. being all of the same nature. are bound to have? To offer them anything inconsistent with their desire will be to grieve them as much as vit would grieve me: so that ifl do harm I must expect to suffer. because there is no reason why others should show more love to me than I have shown to them.