Source: Futility Closet
As an exercise at the end of his 1887 book The Game of Logic, Lewis Carroll presents pairs of premises for which conclusions are to be found:
- No bald person needs a hair-brush; No lizards have hair.
- Some oysters are silent; No silent creatures are amusing.
- All wise men walk on their feet; All unwise men walk on their hands.
- No bridges are made of sugar; Some bridges are picturesque.
- No frogs write books; Some people use ink in writing books.
- Some dreams are terrible; No lambs are terrible.
- All wasps are unfriendly; All puppies are friendly.
- All ducks waddle; Nothing that waddles is graceful.
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