I laughed more than I thought.
Explanation: The joke here plays on the expectations of a philosophy convention versus a comedy show. Philosophy is often seen as serious and thought-provoking, not something that makes people laugh. By going to a combined comedy and philosophy convention, the speaker expected to be more engaged in deep thinking rather than laughing. The punchline is that they “laughed more than they thought,” implying that philosophy turned out to be unexpectedly funny, or that comedy took center stage.