MONISM is a term applied to a group of thinkers or to philosophical systems that emphasize the oneness or unity of reality. Thinkers ordinarily regarded as monists do not themselves use this label, and do not refer to an agreed-upon monistic model. Unlike philosophical systems such as Platonism or Daoism, however, examples of monism cannot be identified by means of an accepted source or criterion. Moreover, in contrast to philosophical schools of thought such as pragmatism or existentialism, monism lacks an identifiable point of origin and a historical framework. In this respect, monism is a conceptual label, like idealism, realism, or determinism. It might be more appropriate to use only the adjectival form: thus, rather than regard a philosophical system as an example of monism, we should understand that, in a variety of ways, philosophical and religious systems are more or less monistic. In view of the arguable...