It is my intent here to establish a groundwork showing that the deontological position pioneered by Immanuel Kant is the most tenable and logically consistent among major ethical theories. Kant broke with other philosophies in two ways: first claiming that ethics must not have any grounding in empirical observation, but rather an entirely rational one; second that ethics should not consider consequences as important in its determination of morality. In one or both of these ways, I will show how Kant disagreed with and refuted the claims of other philosophers in the field of ethics. There will not be room here for a full development of the principles of any of the theories discussed (including deontology), but only for examination in the two areas mentioned.
In substantiating this claim, it is first necessary to know the general scope of ethics. Ethics, I will say, is the philosophical study of what is good or bad, better or worse, and right or wrong, be it action, consequence, or even character. I will be referring specifically to normative ethics, a branch of ethics dealing exclusively with how we ought to be or act (versus descriptive ethics, which tells us how we already are and do act).
Let us consider first some general principles of deontology as proposed by Kant. Kant's fundamental assumption is that morality is universal-that there is a fundamental law dictating what is morally good, and that this law is universally applicable to all rational beings. Kant says that "duty is the necessity of acting from respect for the law." In other words, for someone to do his duty means that he will act in accordance with and recognition of the universal law, and doing his duty is the morally good thing to do.
This brings us to the first point upon which Kant disagrees with other ethical philosophers. Kant says that ethics must be rooted strictly in rational thought, and can have no empirical basis. He reasons that morality is something which only rational beings are capable of, so the basis of morality must be something common to these beings, namely rationality. Further, if this morality is to be universal to rational beings, it must be determinable by any of those beings, thus based solely on their ability to think rationally. If we base our understanding of morality on empirical or observational knowledge, then it can only be determined by different individuals from similar observational knowledge, and is applicable only for particular situations; thus Kant rejected the use of empirical knowledge in the determination of morality. This concept is referred to as a priori judgment, meaning logic-based judgment not based on empirical observation. The opposite of a priori, or judgment based on observation, is known as a posteriori. As just discussed, only in the case that any rational being can reason out a law a priori can it be recognized as a universal law, for only then is it independent of subjective circumstance and experience and thus universal. This point will become clearer by contrast, and will allow us to show why Kant's theory is superior, so let us examine how deontology breaks on this point with other ethical theories.
First we will contrast it with ethical relativism. Relativism claims that there is no universal morality, but rather that morally good actions are those thought to be good within a group, such as a culture or social unit. Kant has many criticisms of such a position. Foremost is that a relativist would have to concede that relative moral theory is exclusively a posteriori. The relativist's proposition could be that two groups of equally rational people could reach diametrically opposite moral views. Since logic should not disagree with equally rational logic, then these differing groups either must use flawed logic or none at all in reaching their moral positions. Granted, relativism could be a tenable position if it could be proven that there is no universal moral law; however, the relativists fail to make such an argument in the normative sense. They claim that there cannot be any universal morality simply because philosophers have not come to agreement upon what it is (or that it does in fact exist). Unfortunately, this claim is fallacious; it commits and error of ad ignoratiam, whereby one assumes that "B" is true only because "A" is unproven, (where "A" is opposite to "B"). In other words, there is no universal morality because no one has proven that there is. It is much more reasonable to accept that there could be a universal law that is universal because it is determinable by any rational being. In consequence of these inconsistent and somewhat illogical claims by relativism, we must accept that deontology presents a superior and more consistent claim.
As a second example of why morality ought to have this a priori logical grounding, we will contrast deontology with utilitarianism. Both agree on the universality of morality, but disagree on the role of empirical judgment. Utilitarian philosophers suggest that "actions are right in proportion as they tend to promote happiness, wrong as they tend to produce the reverse of happiness," or that a good act is one whose consequence maximizes happiness and minimizes unhappiness for the most number of people. Mill, an early utilitarian philosopher, states it thus: "whether mankind do desire nothing for itself but that which is a pleasure to them… [is] a question of fact and experience, dependent… upon evidence." Utilitarianism assumes that happiness is the good that all rational beings should seek, and it is here that deontology disagrees. The support that is presented in defense of the assumption is a posteriori, which Kant and other deontologists find flawed. Utilitarianism fails to show any rational basis for its assumption that pursuing happiness ought to be our aim, aside from the observation that we tend to seek out happiness. (Recall here that normative philosophical theories propose how we ought to be, not how we are; thus the utilitarian assumption that is not normative, but descriptive, does not provide the proper grounding for a normative ethical theory). Even if this was not the case, it would seem redundant for a theory that is supposed to tell us what we ought to seek to base its arguments on what we already seek. Here, I have shown that the claims of deontology again present a more consistent and acceptable claim in terms of rationality.
