Ethical Naturalism

Ethical Naturalism (or Naturalistic Ethics) is the meta-ethical doctrine that there are objective moral properties of which we have empirical knowledge, but that these properties are reducible to entirely non-ethical or natural properties, such as needs, wants or pleasures (as opposed to relating the ethical terms in some way to the will of God, for example).

Ethical Naturalism is a type of Moral Realism and assumes Cognitivism (the view that ethical sentences express propositions and can therefore be true or false). But it goes one step further than Ethical Non-Naturalism, and holds that the meanings of these ethical sentences can be expressed as natural properties without the use of ethical terms (e.g. "good", "right", etc).

It suggests that inquiry into the natural world can increase our moral knowledge in just the same way it increases our scientific knowledge, and that any "ethical value" is confirmable through the methods of science. Moral facts are therefore effectively facts of nature.

Critics complain that a good definition of "natural property" is problematic, but it would normally refer to a property which can be discovered by sense observation or experience, experiment, or through any of the available means of science, and this just does not apply in the case of ethical statements.

The British philosopher G. E. Moore has posed the Open Question Argument in opposition to Ethical Naturalism, in which he states that the question "What is good?" is an open one, as it cannot be answered using natural terms (such as "blue", "rough", "smooth", etc), and yet neither can it be said to have supernatural properties. He termed this a naturalistic fallacy, because the term "good", in the sense of intrinsic value, is effectively indefinable. Moore propounded instead a doctrine of Ethical Non-Naturalism.