Passage Summary: Lawmakers want to label all chemicals used in milk making, but the author says that's a bad idea because you'd have to list every single chemical used on the grass and grain the cows ate.

Conclusion: The proposal to require milk labels to list all artificial substances used in production should not be adopted.

Reasoning: The requirement would be absurdly difficult to satisfy because it would theoretically include every fertilizer and fungicide used in the entire supply chain of the cow's diet.

Analysis: The author employs a 'reductio ad absurdum' approach, identifying a proposal and then extending its logic to an extreme, impractical conclusion. By showing that the literal interpretation of the lawmakers' request would result in an impossibly long list of substances (like fertilizers used on the cow's feed), the author suggests the entire proposal is flawed. Focus on how the argument identifies an unintended and unworkable consequence of the proposed rule to justify its rejection.