12. There are no wholesome plums.
13. Plums are some of them wholesome, and some not.
14. All plums are unwholesome.
[See pp. 59, 60]
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| |
| x
| |
|--y--|
| |
| x'
| |
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__________
Taking y="diligent students"; x="successful";
15. No diligent students are unsuccessful.
16. All diligent students are successful.
17. No students are diligent.