Combining Texts

All the ideas for 'Necessary Existents', 'comedies (frags)' and 'Letter to Weber'

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3 ideas

6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / i. Reals from cuts
I say the irrational is not the cut itself, but a new creation which corresponds to the cut [Dedekind]
     Full Idea: Of my theory of irrationals you say that the irrational number is nothing else than the cut itself, whereas I prefer to create something new (different from the cut), which corresponds to the cut. We have the right to claim such a creative power.
     From: Richard Dedekind (Letter to Weber [1888], 1888 Jan), quoted by Stewart Shapiro - Philosophy of Mathematics 5.4
     A reaction: Clearly a cut will not locate a unique irrational number, so something more needs to be done. Shapiro remarks here that for Dedekind numbers are objects.
19. Language / D. Propositions / 3. Concrete Propositions
Propositions (such as 'that dog is barking') only exist if their items exist [Williamson]
     Full Idea: A proposition about an item exists only if that item exists... how could something be the proposition that that dog is barking in circumstances in which that dog does not exist?
     From: Timothy Williamson (Necessary Existents [2002], p.240), quoted by Trenton Merricks - Propositions
     A reaction: This is a view of propositions I can't make sense of. If I'm under an illusion that there is a dog barking nearby, when there isn't one, can I not say 'that dog is barking'? If I haven't expressed a proposition, what have I done?
22. Metaethics / C. The Good / 1. Goodness / a. Form of the Good
I can form no notion of what the good is [Amphis]
     Full Idea: What the good is I no more can form a notion of, than of the good of Plato.
     From: Amphis (comedies (frags) [c.350 BCE]), quoted by Diogenes Laertius - Lives of Eminent Philosophers 03.1.22
     A reaction: It was evidently a running joke in the ancient world that no one could define Plato's Form of the Good. He was said to have written a book on it, now lost.