Combining Texts

All the ideas for 'works', 'A Problem about Substitutional Quantification?' and 'Laudatio: Prof Ruth Barcan Marcus'

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3 ideas

4. Formal Logic / D. Modal Logic ML / 7. Barcan Formula
If a property is possible, there is something which can have it [Williamson]
     Full Idea: Barcan's axiom says if there can be something that has a certain property, then there is something that can have that property. It and its converse are not obviously correct or incorrect. They claim that it is non-contingent what individuals there are.
     From: Timothy Williamson (Laudatio: Prof Ruth Barcan Marcus [2011], p.1)
     A reaction: Williamson defends the two Barcan formulas, but the more I understand them the less plausible they sound to me.
5. Theory of Logic / G. Quantification / 4. Substitutional Quantification
The substitutional quantifier is not in competition with the standard interpretation [Kripke, by Marcus (Barcan)]
     Full Idea: Kripke proposes that the substitutional quantifier is not a replacement for, or in competition with, the standard interpretation.
     From: report of Saul A. Kripke (A Problem about Substitutional Quantification? [1976]) by Ruth Barcan Marcus - Nominalism and Substitutional Quantifiers p.165
6. Mathematics / B. Foundations for Mathematics / 3. Axioms for Geometry
Archimedes defined a straight line as the shortest distance between two points [Archimedes, by Leibniz]
     Full Idea: Archimedes gave a sort of definition of 'straight line' when he said it is the shortest line between two points.
     From: report of Archimedes (fragments/reports [c.240 BCE]) by Gottfried Leibniz - New Essays on Human Understanding 4.13
     A reaction: Commentators observe that this reduces the purity of the original Euclidean axioms, because it involves distance and measurement, which are absent from the purest geometry.