18. All hungry crocodiles are unamiable.
19. No crocodiles are amiable when hungry.
20. Some crocodiles, when not hungry, are amiable; but some are not.
21. No crocodiles are amiable, and some are hungry.
22. All crocodiles, when not hungry, are amiable; and all unamiable crocodiles are hungry.
23. Some hungry crocodiles are amiable, and some that are not hungry are unamiable.

And who wants to argue with an unamiable crocodile? Lewis’ effort to make syllogisms fun was part of a long tradition. Ever since Aristotle invented them, people have been trying to come up with better ways of representing, manipulating, and teaching syllogisms. Carroll loved logical conundrums, entertaining children, and creating games, so his game was a natural progression. Still, he was (unsurprisingly) aware of the ridiculousness of Aristotelian logic shorn of any context ("Conclusion: Guinea-pigs never really appreciate Beethoven. TRUE or FALSE?"), and Shirky is certainly right that there are limits to what you can do with syllogisms. Classical rhetoric eschews syllogisms in favor of the enthymeme (which lets audiences fill in the middle), natural language (and some artificial ones) introduce ambiguities in meaning, and there are some subjects where the simple attempt to follow premises to their conclusion almost always runs ashore on unstated assumptions. Ask no less a philosopher than Dobie Gillis.

When technology pundit Clay Shirky wanted to attack the idea of the Semantic Web, he didn’t do it the way Cory Doctorow did. Doctorow pointed out that "metadata", information about information, is created by fallable people, people who make mistakes, misjudge what’s important about their work, and have incentives to lie. Shirky went after the underlying technology instead; the Semantic Web, he said, was nothing but a syllogism processing engine. The designer Paul Ford, whose Harper’s Magazine design is one of the first commercial endeavors to be built around Semantic Web principles, strongly disagreed. Ford didn’t mention, however, that Shirky’s examples were very bad syllogisms. Were Shirky playing Lewis Carroll’s "Game of Logic" (its rules proposed in an 1887 pamphlet), he’d be in trouble. It requires proving or disproving statements such as:

18. All hungry crocodiles are unamiable.
19. No crocodiles are amiable when hungry.
20. Some crocodiles, when not hungry, are amiable; but some are not.
21. No crocodiles are amiable, and some are hungry.
22. All crocodiles, when not hungry, are amiable; and all unamiable crocodiles are hungry.
23. Some hungry crocodiles are amiable, and some that are not hungry are unamiable.

And who wants to argue with an unamiable crocodile? Lewis’ effort to make syllogisms fun was part of a long tradition. Ever since Aristotle invented them, people have been trying to come up with better ways of representing, manipulating, and teaching syllogisms. Carroll loved logical conundrums, entertaining children, and creating games, so his game was a natural progression. Still, he was (unsurprisingly) aware of the ridiculousness of Aristotelian logic shorn of any context ("Conclusion: Guinea-pigs never really appreciate Beethoven. TRUE or FALSE?"), and Shirky is certainly right that there are limits to what you can do with syllogisms. Classical rhetoric eschews syllogisms in favor of the enthymeme (which lets audiences fill in the middle), natural language (and some artificial ones) introduce ambiguities in meaning, and there are some subjects where the simple attempt to follow premises to their conclusion almost always runs ashore on unstated assumptions. Ask no less a philosopher than Dobie Gillis.