Passage Summary: Even though a specific habit is good for an individual, we shouldn't tell everyone to do it because the resources would run out, making the habit impossible for everyone.

Conclusion: The universal adoption of a fish-based diet should not be recommended.

Reasoning: Although the diet is healthier, if everyone adopted it, the fish species would go extinct, making the diet impossible to sustain.

Analysis: The reasoning follows a 'self-defeating' structure: an action is beneficial on an individual level, but if performed by everyone, it destroys the very conditions that make the action possible. To find a parallel, look for an argument that rejects a general recommendation because the collective pursuit of that goal would be unsustainable or counterproductive. The abstraction is: 'X is good, but if everyone does X, X becomes impossible; therefore, don't tell everyone to do X.'