Three offhand facts about kittens hide one inevitable logical conclusion
Lewis Carroll loved building chains of odd-sounding premises, called sorites, that hide one inevitable conclusion. Take just three of his: no kitten that loves fish is unteachable; kittens with whiskers always love fish; (ignore the tail-and-gorilla one, it's a distraction from a longer chain). What does the first and second premise together guarantee about every kitten with whiskers?
Reveal the answer
Every kitten with whiskers is teachable. Whiskers guarantee loving fish, and loving fish guarantees being teachable, chain the two together and the middle term 'loves fish' cancels out, leaving a direct link from whiskers to teachability. Carroll built dozens of these tangled syllogisms for his 1896 textbook Symbolic Logic, designed to train readers to spot valid conclusions hidden inside deliberately confusing premises.
— Lewis Carroll (Charles Lutwidge Dodgson), Symbolic Logic — Part I, 1896
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