Contrary to intuitions that human beings are free to think and act with “buck-stopping” freedom, philosophers since Holbach and Hume have argued that universal causation makes free will nonsensical. Contemporary neuroscience has strengthened their case and begun to reveal subtle and counterintuitive mechanisms in the processes of conscious agency. Although some fear that determinism undermines moral responsibility, the opposite is true: free will, if it existed, would undermine coherent systems of justice. Moreover, deterministic views of human choice clarify the conditions (...) in which we ought to protect people from themselves, for example when they cannot give informed consent to medical procedures. Some of the most unresolved questions in this domain are just now emerging; they include robot ethics and the responsibilities of groups. We propose a philosophical and scientific research program to apply complex systems science to these problems. (shrink)