Combining Texts

All the ideas for 'fragments/reports', 'What is Property?' and 'New Foundations for Mathematical Logic'

unexpand these ideas     |    start again     |     specify just one area for these texts


3 ideas

4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / a. Axioms for sets
NF has no models, but just blocks the comprehension axiom, to avoid contradictions [Quine, by Dummett]
     Full Idea: Quine's New Foundations system of set theory, devised with no model in mind, but on the basis of a hunch that a purely formal restriction on the comprehension axiom would block all contradictions.
     From: report of Willard Quine (New Foundations for Mathematical Logic [1937]) by Michael Dummett - Frege philosophy of mathematics Ch.18
     A reaction: The point is that Quine (who had an ontological preference for 'desert landscapes') attempted to do without an ontological commitment to objects (and their subsequent models), with a purely formal system. Quine's NF is not now highly regarded.
9. Objects / C. Structure of Objects / 6. Constitution of an Object
If someone squashed a horse to make a dog, something new would now exist [Mnesarchus]
     Full Idea: If, for the sake of argument, someone were to mould a horse, squash it, then make a dog, it would be reasonable for us on seeing this to say that this previously did not exist but now does exist.
     From: Mnesarchus (fragments/reports [c.120 BCE]), quoted by John Stobaeus - Anthology 179.11
     A reaction: Locke would say it is new, because the substance is the same, but a new life now exists. A sword could cease to exist and become a new ploughshare, I would think. Apply this to the Ship of Theseus. Is form more important than substance?
25. Social Practice / C. Rights / 4. Property rights
Property is theft! [Proudhon]
     Full Idea: Property is theft!
     From: Pierre-Joseph Proudhon (What is Property? [1840]), quoted by Jonathan Wolff - An Introduction to Political Philosophy (Rev)
     A reaction: [Context in Proudhon's book?] This may not be the essence of property rights today, but it is almost undeniable as a historical fact. William the Conqueror kills the opposition in battle, and then gives English land to his friends.