Passage Summary: A philosopher argues that emotions make sense; we just think they don't because our vocabulary is too clumsy to explain the subtle differences between them.

Conclusion: Emotions are not actually nonrational.

Reasoning: Emotions only appear nonrational because our language is too limited to describe them accurately. Our words for emotions are too general, covering broad categories rather than specific experiences.

Analysis: The statement in question—that there is no language to describe how one joy differs from another—is introduced by the phrase 'Thus, for example.' This is a clear indicator that the statement serves as an illustration. It is an example used to support the claim immediately preceding it: that emotional language is too general. That claim, in turn, supports the main conclusion that emotions are not nonrational. When identifying roles, always look for these structural signposts to see how the 'bricks' of the argument build toward the final 'roof' (the conclusion).