Final answer:
Kant argues that consistency and fairness are insufficient for determining moral rules because they overlook the universal nature of the Categorical Imperative and the intricacies of duty-based ethics.
Step-by-step explanation:
Immanuel Kant believes that consistency and fairness fail as tests for determining whether a rule is a moral rule because these tests alone do not fully capture the essence of moral duties. For Kant, the basis for morality should lie in the intention behind the actions—the will to act out of a sense of duty. In his view, moral actions are those that conform to the Categorical Imperative, which suggests actions should be made into universal laws that ration beings would accept. Simply being consistent or fair does not necessarily align with acting out of duty or adhere to the rigors of the Categorical Imperative. Consistency might allow for immoral actions to be consistently performed, and fairness could be subjectively interpreted, thus failing to establish a universally acceptable moral law.
On the other hand, Kant thought Duties are what we must all obligate ourselves to consistently, with some Duties being Perfect (always obligatory) and some Imperfect (obligatory under certain conditions). The issue with the tests of consistency and fairness is that they fail to consider the pluralistic nature of moral obligations and the sometimes conflicting competing duties we face in complex moral situations. Kant's Categorical Imperative, especially in its universal law formulation, demands that actions must be justifiable as a law for all and not merely consistent or subjectively fair.