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2 ideas
| 8822 | Statements about necessities need not be necessarily true [Pollock] |
| Full Idea: True statements about the necessary properties of things need not be necessarily true. The well-known example is that the number of planets (9) is necessarily an odd number. The necessity is de re, but not de dicto. | |
| From: John L. Pollock (Epistemic Norms [1986], 'Nat.Internal') | |
| A reaction: This would be a matter of the scope (the placing of the brackets) of the 'necessarily' operator in a formula. The quick course in modal logic should eradicate errors of this kind in your budding philosopher. |
| 11965 | Could possible Adam gradually transform into Noah, and vice versa? [Chisholm] |
| Full Idea: If Adam lived for 931 years in a possible world, instead of his actual 930 years, ..then Adam and Noah could gradually exchange their ages and other properties...and we could trace Adam in a world back to the actual Noah, and vice versa. | |
| From: Roderick Chisholm (Identity through Possible Worlds [1967], p.81-2) | |
| A reaction: [very compressed] Chisholm was one of the first to raise this problem for possible worlds, though it had been Quine's objection to modal logic all along. Only Adam having essential properties seems to stop this slippery slope, says Chisholm. |