There are a number of versions of how Chrysippus died, one of which says he drank some overproof wine while another says that he died of laughter*.
Apparently, he died laughing at his own joke. The story goes something like this*:
...one day on his way home Chrysippus came across an ass eating figs. He instructed the old woman who lived with him to give the ass some unmixed wine to drink afterwards, and with that he laughed so violently he died.
Or according to Wikipedia*:
In the second account, he was watching a donkey eat some figs and cried out: "Now give the donkey a drink of pure wine to wash down the figs", whereupon he died in a fit of laughter.
I don't know if it is the zeitgeist or some weird Stoic sense of humor but the joke is completely lost on me. I found multiple sources telling the story, but none provided an explanation.
Can someone explain why somebody in that time period (ca. 200 BC) would find that joke hilarious?