Passage Summary: You can't tell people not to be 'unnatural' because that word either means 'impossible' (so they couldn't do it anyway) or 'unusual' (which isn't a good reason to stop).

Conclusion: The claim that people are morally obligated to avoid 'unnatural' actions is absurd.

Reasoning: The term 'unnatural' either means a violation of physical laws (which is impossible) or a statistical rarity (which is not a moral reason to avoid something).

Analysis: The philosopher employs a technique of 'exhaustive definition' to dismantle the opposing view. By breaking the opponent's key term into its only two possible meanings and showing that neither meaning supports the opponent's conclusion, the philosopher renders the original argument toothless. When identifying the method of reasoning, focus on how the author analyzes the implications of a specific concept to show it is insufficient for the claim being made. It is a very tidy way of cornering an opponent by their own vocabulary.