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| | 0 |
| ---|--- |
| | 0 | 0 | |
13. |-1-|---|---|---| -------
| | | | | | | 0 |
| ---|--- | |---|---|
| | 0 | | | |
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Let "books" be Universe; m="exciting",
x="that suit feverish patients"; y="that make
one drowsy".
No m are x; &there4 No y' are x.
All m' are y.
i.e. No books suit feverish patients, except such as make
one drowsy.