Optimal choice is a basic principle of most systems of morality that have any pretence to philosophical rigor. For example, in utilitarianism, according to Jeremy Bentham, "[Joseph] Priestley was the first (unless it was Beccaria) who taught my lips to pronounce this sacred truth:- That the greatest happiness of the greatest number is the foundation of morals and legislation." However, it was quickly realized by Bentham that zero-sum considerations require us to qualify that principle, so that what is actually maximized is happiness itself.
Since utilitarians judge all actions by their ability to maximize good consequences, any harm to one individual can always be justified by a greater gain to other individuals. This is true even if the loss for the one individual is large and the gain for the others is marginal, as long as enough individuals receive the small benefit. Thus, utilitarians deny that individuals have inviolable moral rights. As explained above, utilitarians may support legal rights or rights as rules of thumb, but they are not considered inherent to morality. This seems problematic to many critics of utilitarianism, one of whom notes that according to utilitarianism there is "nothing intrinsically wrong with sacrificing an important individual interest to a greater sum of lesser interests. That assumption is retained in the foundations of the theory, and it remains a source of moral concern."
Although the above criticism may not be, two other related criticisms of utilitarianism are based on misconceptions. The principle of "the greatest good for the greatest number", introduced by Bentham, is often mistaken as meaning that if something hurts one person and helps many, it is always moral. This is not the case, however; as noted above, Bentham dropped the misleading "greatest number" part of the principle, replacing the original formulation with the more direct "greatest happiness principle." Thus, the morality of an action is not determined by the number of people made happier, but rather the quantity of happiness produced. A great loss to one individual might be outweighed by small gains for many, but it might not. Even if 1 person is hurt and 100 people are helped, the harm to the one might be so great as to outweigh the small gains for the rest of the people.
It is, of course, well known that even this more nuanced approach flies in the face of the basic Catholic principle that one may not do evil in order that good may result. The moral calculus of when, for example, eminent domain is permissible to apply is not so trivial as this most basic of utilitarian principles.
Indeed, the moral calculus is fundamentally non materialistic. According to Immanuel Kant (not my favorite philosopher by any means, yet he was often able to see the obvious)
The idea of the highest good, inseparably bound up with the purely moral disposition, cannot be realized in man himself ... yet he discovers within himself the duty to work for this end. Hence he finds himself impelled to believe in the cooperation or management of a moral Ruler of the world, by means of which this goal can be reached. And now there opens up before him the abyss of a mystery regarding what God may do . . . , whether indeed anything in general, and if so, what in particular should be ascribed to God. [Religion within the Limits of Reason Alone, Harper and Row, 1960, p. 130. Quoted in "Kant on Reason and Religion."]
The question is, of course, what constitutes the "highest good." Kant's observation points us in the right direction, almost. Instead of considering the Creator's cooperation in the human venture, however, it would have been better to regard the obverse enterprise, namely, to consider human cooperation in God's plans.
Any theory of Natural Law which acknowledges its roots in natural theology will incorporate, then, the following considerations:
We may refer to the goal of advancing furthest along God's plan, in the above sense, to be to "Seek the highest good."