contains "Some rainy days are tiresome", which contains "Some rainy periods are tiresome".
Moreover, the first Premiss, besides being superfluous, is actually contained in the second; since it is equivalent to "Some rainy days exist", which, as we know, is implied in the Proposition "All rainy days are tiresome".
Altogether, a most unsatisfactory Pair of Premisses!
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| 0 | |
| ---|--- |
| | 1 | | |
20. |---|---|---|---| -------
| | 0 | 0 | | | 1 | |
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| 0 | | | 0 | |
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