In
ethics, the view that propositions about value may deductively follow from propositions about factual states of affairs,
contra the
Humean dictum that
"you can't get ought from is."
An example of a naturalistic ethic is utilitarianism, where the good is said to inhere in the greatest happiness of the greatest number of people, or some similar supposedly measurable quantity.
Ethical non-naturalism opposes this way of allowing true statements about values, but nonetheless holds value to be real.