I discuss first the meaning of naturalism in philosophy and then the sense in which it has
been introduced in ethics: that of American Naturalism, that of Dewey’s pragmatism, the
sense of a negation of Moore’s negation of naturalism, the neo-Aristotelian, and the one of
the external realists. I will argue a fundamental heterogeneity of these meanings and will
add that the reasons for the apparent unity of a naturalist front in recent philosophical
debates lies more in factors pertaining to the sociology of knowledge. I will suggest that
there is one sense in which a naturalism claim may be defended, the sense of Aristotle and
Dewey, according to which moral good is not specifically moral in its nature. I will add that
programs of scientific exploration into biological bases of behaviour and co-ordination of
behaviour within groups are highly promising, but are in no sense ‘naturalistic’ and are
indeed compatible with ethical intuitionism, or Kantian ethics.
