  It is important, however, to distinguish in this regard between two different kinds of moral naturalism. One kind maintains that moral properties are identical with certain natural properties specified by combinations of non-moral terms found in the natural and social sciences (Brandt 1979, Railton 1986, Copp 1995). To take an oversimplified example, suppose that the property of being a wrong act is identical with the property of having as a consequence a lower quotient of pleasure over pain for all affected by the act than an alternative act would. Here a moral property of being a wrong act is held to be one and the same property as a complex utilitarian property specified in the non-moral terms of consequence, pleasure, and pain. Given this identity, an act having this moral property cannot be less open to empirical study nor can it have less explanatory power than an act’s having the property of not maximizing pleasure over pain. For instance, if a group avoids a certain kind of action, the correct explanation, given the identity and the role of pleasure and pain in learning, could be that this kind of act is wrong. Whether it is or not would be an empirical question.