“Moral worth should be judged not in terms of the naturalness of a trait, but rather in terms of how that trait impacts the wellbeing of everyone affected by it. Thus, violence is natural but bad, medicine unnatural but good.”
– Steve Stewart-Williams, The Ape that Understood the Universe
道德与否不应该以某一属性是否自然为依据，而是应该以该属性是否会影响所有人的福祉为据。正因为如此，暴力是自然的却是不对的，医药是非自然的却是好的。