In our first Utilitarian Reasoning, we saw the clear resonance that Utilitarian conceptions of justice had with Epicurean conceptions of mutual advantage, as presented in the Principal Doctrines. In Mill’s fifth chapter, the subject of justice is revisited, as it relates to duty and where duty is born from. Utilitarianism, like Epicureanism, seems to favor a contractarian approach. Both philosophies therefore reject deontological views of morality, which posit that all morality is born of blind duty, which is generally understood to exist as a result of our place in society. Duty exists, they say, but only as a result of utility; that is to say, of mutual advantage as expressed in agreements between civilized parties.
It is a part of the notion of Duty in every one of its forms, that a person may rightfully be compelled to fulfil it. Duty is a thing which may be exacted from a person, as one exacts a debt. Unless we think that it may be exacted from him, we do not call it his duty.
… No one has a moral right to our generosity or beneficence, because we are not morally bound to practise those virtues towards any given individual.
… To have a right, then, is, I conceive, to have something which society ought to defend me in the possession of. If the objector goes on to ask, why it ought? I can give him no other reason than general utility.
Justice remains the appropriate name for certain social utilities which are vastly more important, and therefore more absolute and imperative, than any others are as a class … distinguished from the milder feeling which attaches to the mere idea of promoting human pleasure or convenience, at once by the more definite nature of its commands, and by the sterner character of its sanctions.