Utilitarian Ethical Theory (UET) is not one theory; it is a cluster of theories which share the key assumption that morality is a matter of consequences. Below is a summery of all the utilitarian theories we have considered so far. There are others, but these will do for our study of ethics.
| UET | Hedonic | Eudaimonic | Ideal | Preferential |
| Act | HAU: An action X is morally right iff X promotes at least as great a balance of pleasure over pain for the greatest number of people, considered equally, as any alternative action. | EAU: An action X is morally right iff X promotes at least as great a balance of happiness over unhappiness for the greatest number of people, considered equally, as any alternative action. | IAU: An action X is morally right iff X promotes at least as much of the best interests of the greatest number of people, considered equally, as any alternative action. | PAU: An action X is morally right iff X promotes at least as many of the preferences of the greatest number of people, considered equally, as any alternative action. |
| Rule | HRU: An action X is morally right iff X is in accord with a rule R, where R is an essential member of a set of rules S such that S, when followed, promotes at least as great a balance of pleasure over pain for the greatest number of people, considered equally, as any alternative set of rules. | ERU: An action X is morally right iff X is in accord with a rule R, where R is an essential member of a set of rules S such that S, when followed, promotes at least as great a balance of happiness over unhappiness for the greatest number of people, considered equally, as any alternative set of rules. | IRU: An action X is morally right iff X is in accord with a rule R, where R is an essential member of a set of rules S such that S, when followed, promotes at least as much of the best interests of the greatest number of people, considered equally, as any alternative set of rules. | PRU:An action X is morally right iff X is in accord with a rule R, where R is an essential member of a set of rules S such that S, when followed, promotes at least as many preferences of the greatest number of people, considered equally, as any alternative set of rules. |