Ethics without Free Will Aaron L Bramson Abstract Moral theories typically rest upon the assumption that conscious deliberation plays a causal role in action; however, a growing body of scientific evidence supports a physi- calist account of causation that leaves no causal role for mental activity. In response, I develop a moral theory (including moral truth, motivation, and meaning) that excludes considerations of conscious free will. I then consider how an acceleration in social evolu- tion compared with biological evolution affected our moral knowledge and motivations. The idea of a normative model is offered to replace normative ethical theorizing, and finally various problems of the theory are identified for future work. 1 Introduction The combination of 1) appealing reductionist arguments from metaphysics and 2) recent scientific discoveries in psychology, neurology, bio-chemistry, and physics gives strong sup- port to a physicalist account of behavior devoid of any ghost in the machine. If the thesis that mental states are irrelevant to human behavior is defendable, then any philosophical ethical theory that hinges on humans’ ability to act intentionally fails to provide a proper foundation for moral truth, meaning, and motivation. Much of the recent work in ethical theory has focused on the relation of reasons to motivation and action, but only in the context of particular (though varying) models of psychology. By taking seriously the evo- lutionary origins of emotions, ethical intuitions, and physical responses I develop a theory of moral meaning, truth, and motivation independently of humans’ ability to act through conscious free will. The question of the evolution of human society and morality is an old one. When and how did humans develop the ability to regulate our activity according to social norms? Are humans unique in our development of morality and ethical principles? What facts about human nature (the biologically determined aspects of human beings) are relevant to moral thinking and action? This paper is an attempt to use principles from modern evolutionary theory to flesh out something like the following story of Machiavelli’s. These various kinds of government came into existence among men by chance, for in the beginning of the world, the inhabitants being few, they lived dispersed for a time in the manner of beasts. Then, as the population increased, they drew together and, the better to defend themselves, they sought out the strongest and bravest one among them, made him their leader, and obeyed him. From this 1