Abstract

The aim of this thesis is to examine the strength of various philosophical answers to the question, "Why by moral?" In my introduction, I consider the suggestion from certain sociobiologists that whether or not an individual will behave morally may be genetically determined. I reject this possibility on the grounds that the requirements for moral behavior are not reducible to genetically-encoded character traits, and genetic influence does not fully determine human behavior. In Part I: Pure Reason, I address arguments, primarily those from Immanuel Kant and Derek Parfit, which purport to show that either pure reason or perfect rationality requires an acceptance of moral constraint. I demonstrate that while some of these arguments are internally flawed, even those which are valid cannot provide a consistent source of moral motivation to appeal to any rational, intelligent, and informed individual, because they presuppose the individual's commitment to morality. In Part II: Self-Interest, I define rational self-interest and then analyze arguments from several contemporary ethicists which attempt to show that the achievement of maximum personal utility requires the acceptance of moral constraint. Although I am persuaded that the demands of morality and self-interest will coincide when certain conditions are met , it is clear that many circumstances remain in which an individual can maximize his utility without accepting moral constraint. In Part III: Emotions and Character, I pursue the idea that effective, character-based moral instruction may help to shore up the motivational gap by creating a set of emotional costs and benefits associated with moral behavior, such that the morally educated individual will not be able to maximize her utility without behaving morally. However, I conclude that there will always be individuals who escape society's efforts to instill them with a desire to behave morally, and these individuals will have no consistent, rationally compelling, good reason to be moral