““Following nature means following the facts. It means getting the facts about the physical and social world we inhabit, and the facts about our situation in it—our own powers, relationships, limitations, possibilities, motives, intentions, and endeavors—before we deliberate about normative matters. It means facing those facts—accepting them for exactly what they are, no more and no less—before we draw normative conclusions from them. It means doing ethics from the facts—constructing normative propositions a posteriori. It means adjusting those normative propositions to fit changes in the facts, and accepting those adjustments for exactly what they are, no more and no less. And it means living within the facts—within the realm of actual rather than hypothetical norms.””
