Ethical non-naturalism

Ethical non-naturalism is the meta-ethical view which claims that:

This makes ethical non-naturalism a non-definist form of moral realism, which is in turn a form of cognitivism. Ethical non-naturalism stands in opposition to ethical naturalism, which claims that moral terms and properties are reducible to non-moral terms and properties, as well as to all forms of moral anti-realism, including ethical subjectivism (which denies that moral propositions refer to objective facts), error theory (which denies that any moral propositions are true), and non-cognitivism (which denies that moral sentences express propositions at all).

According to G. E. Moore, "Goodness is a simple, undefinable, non-natural property." To call goodness "non-natural" does not mean that it is supernatural or divine. It does mean, however, that goodness cannot be reduced to natural properties such as needs, wants or pleasures. Moore also stated that a reduction of ethical properties to a divine command would be the same as stating their naturalness. This would be an example of what he referred to as "the naturalistic fallacy."

Moore claimed that goodness is "indefinable", i.e., it cannot be defined in any other terms. This is the central claim of non-naturalism. Thus, the meaning of sentences containing the word "good" cannot be explained entirely in terms of sentences not containing the word "good." One cannot substitute words referring to pleasure, needs or anything else in place of "good."

Some properties, such as hardness, roundness and dampness, are clearly natural properties. We encounter them in the real world and can perceive them. On the other hand, other properties, such as being good and being right, are not so obvious. A great novel is considered to be a good thing; goodness may be said to be a property of that novel. Paying one's debts and telling the truth are generally held to be right things to do; rightness may be said to be a property of certain human actions.

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