The three basic ethical theories share a number of similarities, because they each attempt to describe and explicate the ethical decisions made by humans as well as the logic (or illogic) that is used to inform any particular behavior. Utilitarianism offers what is perhaps the most sound ethical theory due to the way it chooses for itself the goal of its efforts, but it is hampered by disagreement regarding the precise execution of the theory. A deontological theory of ethics may be useful for formulating general rules regarding proper behavior, and as such is popular is the workplace, but these rules are not universally applicable and in some cases can actually lead to unethical behavior if followed without fail. Finally, while virtues-based ethics purports to offer individuals instruction for the cultivation of ideal behavioral traits, by definition it cannot offer a universal ethical norm, as it is based on the contemporary social norms of the day, regardless of their relation to any universal set of ethics. After comparing and contrasting the three major ethical theories, it becomes clear that only utilitarianism can offer the kind of self-correcting mechanism necessary for any ethical theory to be both consistent and universally ethical, regardless of how much information the individual has or the particulars of any given situation.
Utilitarianism makes a central presumption regarding the intended role of ethics, but this presumption is rarely discussed and as such has led to much of the confusion and debate surrounding the subject. While other ethical theories purport to describe phenomenon they consider to be inherent, objective standards of behavior or intention, utilitarianism presumes that there is no genuinely objective set of ethical standards, but rather only what amounts to best practices for achieving a certain goal. In this sense, "utilitarianism, unlike rival moral theories, is often thought to be compatible with a metaphysics shorn of any mysterious, intrinsically normative properties which might stand outside of a physical, mechanistic nature," and as such representative of "a supposed congruence [with] a modern scientific world view" (Mandle, 1999, p. 538). For some, this is an uncomfortable proposition, because they find it bleak to imagine that there is no inherent meaning or moral standard in the universe, but in reality this position merely frees utilitarianism, as an ethical theory, to expand and correct itself based upon the accumulation of more knowledge.
After recognizing that ethical theories function not so much a description of objective ethical or moral truths but instead are invented, emergent means of modulating behavior, it simply becomes a matter of determining what the agreed-upon goal of human behavior is and the best ways of modulating behavior in order to meet that goal. Some unnecessary debate has sprung from this point, because for many philosophers, the decision to choose the greatest happiness as the goal, aside from being a relatively ill-defined concept, appears arbitrary and born out of a lingering commitment to preexisting, non-naturalistic ethical theories (Riley, 2009, p. 286). However, this mistakes a problem on the part of certain writers with a problem inherent in the theory, because the choice of the greatest happiness as the goal of human behavior is entirely natural, and in fact expected, when one considers that human beings have evolved, over millions of years, to become a highly social species, and just as one may breed moral behavioral traits like altruism into animals through domestication and socialization, so too have humans developed certain standards of behavior that maximize the social group's chance of success. Of course, this does not mean that utilitarianism argues that any particular individual should automatically feels any desire to contribute to the larger benefit of the group, but rather illustrates how the utilitarian decision to value the greatest happiness, however that is defined, is logical based on the general trends of human behavior that have evolved over millions of years.
In this sense, the basis for utilitarianism's choice of the greatest happiness as the goal of its ethical system is a kind of ethical anthropic principle, in that it is almost unremarkable that one may observe a seemingly "natural" tendency towards ethics, because if it were any other way human beings would have had to evolved as an entirely different species. Thus, utilitarianism is also able to account for the fact that other ethical theories, while wrong about the existence of objective moral standards, nevertheless have succeeded in codifying some of the same general standards that might be found in the utilitarian framework; these congruences are not evidence of utilitarianism holding on to the standards of preexisting ethical systems, but rather reveals that these preexisting ethical systems quite naturally included a number of utilitarian ethical values, misattributed to the existence of objective moral value rather than evolutionary emergence. Put another way, utilitarianism recognizes that "all of the explanatory work we need can ultimately be provided by the tools and vocabulary of the natural sciences," and as such, other ethical theories may be viewed as incomplete but nevertheless beneficial evolutionary adaptations (Mandle, 1999, p. 539).
At this point it may appear that utilitarianism is a completely sound ethical theory, and indeed, of the three theories to be discussed here, it is the only one which offers a consistent and universally applicable ethical standard, but this does not mean that the theory does not have it weaknesses. In fact, one might say that its greatest strength, which is the self-correcting mechanism of being dependent on the accumulation of knowledge in order to inform decision-making, is also its greatest weakness due to the fact that individuals rarely have all of the information necessary to make a completely informed decision regarding any particular situation. This has led to a split between so-called rule utilitarianism and act utilitarianism, with the former focusing on the use of general rules in lieu of perfect knowledge regarding the outcome of a behavior, while the latter accepts that knowledge can never be complete, but that this fact should not preclude one from attempting to bring about the best possible consequences given the knowledge at hand (Palmer, 1999, p. 33). Ultimately, it seems unlikely that rule utilitarianism can ever be a truly viable interpretation, because the dependence on the existence of a strong rule independent of the good produced by it in every circumstance means that one must be able to observe and define "a fairly limited number of rules that are easily applicable and have few exceptions," and evidence and experience shows this to be impossible (Palmer, 1999, p. 41). Act utilitarianism, on the other hand, is concerned "solely with the characteristics that make an action right" according to the predetermined goal of that action, and as such makes no judgment regarding the existence of standardized rules except to acknowledge that certain "rules of thumb" are often used to supplement one's knowledge when faced with any given situation, but that even then these rules of thumb may not necessarily lead one to make the most ethical decision (Palmer, 1999, p. 40). This theoretical split between rule utilitarianism and act utilitarianism has kept the theory as a whole from developing an effective argument for its validity, because the existence of rule utilitarianism as a theory actually serves to cloud the issue and unnecessarily impugn act utilitarianism.
Nevertheless, utilitarianism remains the most useful of the three major ethical theories, but to understand why, it is necessary to examine the other two in greater detail. Deontological ethics is an ethical theory that argues for the existence of ethical rules, and suggests that morality comes from adherence to these rules. As such, deontological theories "privilege a discourse of 'rights' and 'individual' autonomy" when considering ethical behavior and the supposed rules which inform it (Franks, 2008, p. 135). The theory argues that "only the one who becomes 'universalizable' in his/her actions in the sense of acting upon a maxim that could serve as a maxim for all human beings in comparable situations […] is truly free," and in doing so reveals one of its key flaws; namely, that no such maxims actually exist, or at least have not been sufficiently observed or proposed, and thus the theory is ultimately dependent on subjective determinations of supposedly objective standards (Micewski & Troy, 2007, p. 23).
The term was first used by Broad (1930) to describe those ethical theories which argue "that the notion of fittingness is fundamental, and that "X is intrinsically good" means that it is fitting for every rational being to desire X" (Broad, 1930, p. 278). In many ways, this is a distilled version of religious arguments for moral superiority, which depend upon the existence of a god who dictates moral standards, but in this case deontological arguments merely avoid attempting to explain where these objective ethical standards might have come from and instead focus on defining and codifying these perceived objective standards. At this point one can see the clear advantage utilitarianism has over deontological ethics; while deontological ethics cannot account for the cause of its supposed…