Progress may be made in resolving the tension between free will and determinism by analysis of the necessary conditions of freedom. It is of the essence that these conditions include causal and deterministic regularities. Furthermore, the human expression of free will is informed by understanding some of those regularities, and increments in that understanding have served to enhance freedom. When the possible character of a deterministic system based on physical theory is considered, it is judged that, far from implying the elimination of human freedom, such a theory might simply set parameters for it; indeed knowledge of that system could again prove to be in some respects liberating. On the other hand, it is of the essence that the overar...