Combining Texts

All the ideas for 'Investigations in the Foundations of Set Theory I', 'Varieties of Things' and 'on Goodman's 'Ways of Worldmaking''

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47 ideas

1. Philosophy / D. Nature of Philosophy / 5. Aims of Philosophy / d. Philosophy as puzzles
Philosophy tries to explain how the actual is possible, given that it seems impossible [Macdonald,C]
1. Philosophy / F. Analytic Philosophy / 5. Linguistic Analysis
'Did it for the sake of x' doesn't involve a sake, so how can ontological commitments be inferred? [Macdonald,C]
2. Reason / D. Definition / 8. Impredicative Definition
Predicative definitions are acceptable in mathematics if they distinguish objects, rather than creating them? [Zermelo, by Lavine]
2. Reason / F. Fallacies / 5. Fallacy of Composition
Don't assume that a thing has all the properties of its parts [Macdonald,C]
4. Formal Logic / F. Set Theory ST / 1. Set Theory
We take set theory as given, and retain everything valuable, while avoiding contradictions [Zermelo]
Set theory investigates number, order and function, showing logical foundations for mathematics [Zermelo]
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / a. Axioms for sets
ZFC: Existence, Extension, Specification, Pairing, Unions, Powers, Infinity, Choice [Zermelo, by Clegg]
Zermelo published his axioms in 1908, to secure a controversial proof [Zermelo, by Maddy]
Set theory can be reduced to a few definitions and seven independent axioms [Zermelo]
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / c. Axiom of Pairing II
Zermelo introduced Pairing in 1930, and it seems fairly obvious [Zermelo, by Maddy]
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / i. Axiom of Foundation VIII
Zermelo used Foundation to block paradox, but then decided that only Separation was needed [Zermelo, by Maddy]
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / m. Axiom of Separation
The Axiom of Separation requires set generation up to one step back from contradiction [Zermelo, by Maddy]
Not every predicate has an extension, but Separation picks the members that satisfy a predicate [Zermelo, by Hart,WD]
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / e. Ordinal numbers
In ZF, the Burali-Forti Paradox proves that there is no set of all ordinals [Zermelo, by Hart,WD]
6. Mathematics / B. Foundations for Mathematics / 5. Definitions of Number / f. Zermelo numbers
For Zermelo the successor of n is {n} (rather than n U {n}) [Zermelo, by Maddy]
6. Mathematics / B. Foundations for Mathematics / 6. Mathematics as Set Theory / a. Mathematics is set theory
Zermelo believed, and Von Neumann seemed to confirm, that numbers are sets [Zermelo, by Maddy]
6. Mathematics / B. Foundations for Mathematics / 7. Mathematical Structuralism / e. Structuralism critique
Different versions of set theory result in different underlying structures for numbers [Zermelo, by Brown,JR]
7. Existence / C. Structure of Existence / 2. Reduction
Reduce by bridge laws (plus property identities?), by elimination, or by reducing talk [Macdonald,C]
7. Existence / D. Theories of Reality / 6. Physicalism
Every worldly event, without exception, is a redistribution of microphysical states [Quine]
8. Modes of Existence / A. Relations / 2. Internal Relations
Relational properties are clearly not essential to substances [Macdonald,C]
8. Modes of Existence / A. Relations / 4. Formal Relations / a. Types of relation
Being taller is an external relation, but properties and substances have internal relations [Macdonald,C]
8. Modes of Existence / B. Properties / 12. Denial of Properties
Does the knowledge of each property require an infinity of accompanying knowledge? [Macdonald,C]
8. Modes of Existence / B. Properties / 13. Tropes / a. Nature of tropes
Tropes are abstract (two can occupy the same place), but not universals (they have locations) [Macdonald,C]
Properties are sets of exactly resembling property-particulars [Macdonald,C]
Tropes are abstract particulars, not concrete particulars, so the theory is not nominalist [Macdonald,C]
8. Modes of Existence / B. Properties / 13. Tropes / b. Critique of tropes
How do a group of resembling tropes all resemble one another in the same way? [Macdonald,C]
Trope Nominalism is the only nominalism to introduce new entities, inviting Ockham's Razor [Macdonald,C]
8. Modes of Existence / D. Universals / 2. Need for Universals
Numerical sameness is explained by theories of identity, but what explains qualitative identity? [Macdonald,C]
8. Modes of Existence / D. Universals / 6. Platonic Forms / b. Partaking
How can universals connect instances, if they are nothing like them? [Macdonald,C]
8. Modes of Existence / E. Nominalism / 1. Nominalism / c. Nominalism about abstracta
Real Nominalism is only committed to concrete particulars, word-tokens, and (possibly) sets [Macdonald,C]
8. Modes of Existence / E. Nominalism / 2. Resemblance Nominalism
Resemblance Nominalism cannot explain either new resemblances, or absence of resemblances [Macdonald,C]
9. Objects / A. Existence of Objects / 5. Individuation / c. Individuation by location
A 'thing' cannot be in two places at once, and two things cannot be in the same place at once [Macdonald,C]
9. Objects / A. Existence of Objects / 5. Individuation / e. Individuation by kind
We 'individuate' kinds of object, and 'identify' particular specimens [Macdonald,C]
9. Objects / B. Unity of Objects / 2. Substance / a. Substance
Unlike bundles of properties, substances have an intrinsic unity [Macdonald,C]
9. Objects / B. Unity of Objects / 2. Substance / d. Substance defined
The bundle theory of substance implies the identity of indiscernibles [Macdonald,C]
9. Objects / B. Unity of Objects / 2. Substance / e. Substance critique
A phenomenalist cannot distinguish substance from attribute, so must accept the bundle view [Macdonald,C]
When we ascribe a property to a substance, the bundle theory will make that a tautology [Macdonald,C]
Substances persist through change, but the bundle theory says they can't [Macdonald,C]
A substance might be a sequence of bundles, rather than a single bundle [Macdonald,C]
9. Objects / B. Unity of Objects / 3. Unity Problems / c. Statue and clay
A statue and its matter have different persistence conditions, so they are not identical [Macdonald,C]
9. Objects / C. Structure of Objects / 7. Substratum
A substance is either a bundle of properties, or a bare substratum, or an essence [Macdonald,C]
Each substance contains a non-property, which is its substratum or bare particular [Macdonald,C]
The substratum theory explains the unity of substances, and their survival through change [Macdonald,C]
A substratum has the quality of being bare, and they are useless because indiscernible [Macdonald,C]
9. Objects / F. Identity among Objects / 7. Indiscernible Objects
At different times Leibniz articulated three different versions of his so-called Law [Macdonald,C]
The Identity of Indiscernibles is false, because it is not necessarily true [Macdonald,C]
16. Persons / D. Continuity of the Self / 2. Mental Continuity / b. Self as mental continuity
In continuity, what matters is not just the beginning and end states, but the process itself [Macdonald,C]