29 ideas
| 8679 | We perceive the objects of set theory, just as we perceive with our senses [Gödel] |
| Full Idea: We have something like perception of the objects of set theory, shown by the axioms forcing themselves on us as being true. I don't see why we should have less confidence in this kind of perception (i.e. mathematical intuition) than in sense perception. | |
| From: Kurt Gödel (What is Cantor's Continuum Problem? [1964], p.483), quoted by Michčle Friend - Introducing the Philosophy of Mathematics 2.4 | |
| A reaction: A famous strong expression of realism about the existence of sets. It is remarkable how the ingredients of mathematics spread themselves before the mind like a landscape, inviting journeys - but I think that just shows how minds cope with abstractions. |
| 9942 | Gödel proved the classical relative consistency of the axiom V = L [Gödel, by Putnam] |
| Full Idea: Gödel proved the classical relative consistency of the axiom V = L (which implies the axiom of choice and the generalized continuum hypothesis). This established the full independence of the continuum hypothesis from the other axioms. | |
| From: report of Kurt Gödel (What is Cantor's Continuum Problem? [1964]) by Hilary Putnam - Mathematics without Foundations | |
| A reaction: Gödel initially wanted to make V = L an axiom, but the changed his mind. Maddy has lots to say on the subject. |
| 10405 | In the iterative conception of sets, they form a natural hierarchy [Swoyer] |
| Full Idea: In the iterative conception of sets, they form a natural hierarchy. | |
| From: Chris Swoyer (Properties [2000], 4.1) |
| 10407 | Logical Form explains differing logical behaviour of similar sentences [Swoyer] |
| Full Idea: 'Logical Form' is a technical notion motivated by the observation that sentences with a similar surface structure may exhibit quite different logical behaviour. | |
| From: Chris Swoyer (Properties [2000], 4.2) | |
| A reaction: [Swoyer goes on to give some nice examples] The tricky question is whether each sentence has ONE logical form. Pragmatics warns us of the dangers. One needs to check numerous inferences from a given sentences, not just one. |
| 18062 | Set-theory paradoxes are no worse than sense deception in physics [Gödel] |
| Full Idea: The set-theoretical paradoxes are hardly any more troublesome for mathematics than deceptions of the senses are for physics. | |
| From: Kurt Gödel (What is Cantor's Continuum Problem? [1964], p.271), quoted by Philip Kitcher - The Nature of Mathematical Knowledge 03.4 |
| 10868 | The Continuum Hypothesis is not inconsistent with the axioms of set theory [Gödel, by Clegg] |
| Full Idea: Gödel proved that the Continuum Hypothesis was not inconsistent with the axioms of set theory. | |
| From: report of Kurt Gödel (What is Cantor's Continuum Problem? [1964]) by Brian Clegg - Infinity: Quest to Think the Unthinkable Ch.15 |
| 13517 | If set theory is consistent, we cannot refute or prove the Continuum Hypothesis [Gödel, by Hart,WD] |
| Full Idea: Gödel proved that (if set theory is consistent) we cannot refute the continuum hypothesis, and Cohen proved that (if set theory is consistent) we cannot prove it either. | |
| From: report of Kurt Gödel (What is Cantor's Continuum Problem? [1964]) by William D. Hart - The Evolution of Logic 10 |
| 10271 | Basic mathematics is related to abstract elements of our empirical ideas [Gödel] |
| Full Idea: Evidently the 'given' underlying mathematics is closely related to the abstract elements contained in our empirical ideas. | |
| From: Kurt Gödel (What is Cantor's Continuum Problem? [1964], Suppl) | |
| A reaction: Yes! The great modern mathematical platonist says something with which I can agree. He goes on to hint at a platonic view of the structure of the empirical world, but we'll let that pass. |
| 10421 | Supervenience is nowadays seen as between properties, rather than linguistic [Swoyer] |
| Full Idea: Supervenience is sometimes taken to be a relationship between two fragments of language, but it is increasingly taken to be a relationship between pairs of families of properties. | |
| From: Chris Swoyer (Properties [2000], 7.17) | |
| A reaction: If supervenience is a feature of the world, rather than of our descriptions, then it cries out for explanation, just as any other regularities do. Personally I would have thought the best explanation of the supervenience of mind and body was obvious. |
| 10410 | Anti-realists can't explain different methods to measure distance [Swoyer] |
| Full Idea: Anti-realists theories of measurement (like operationalism) cannot explain how we can use different methods to measure the same thing (e.g. lengths and distances in cosmology, geology, histology and atomic physics). | |
| From: Chris Swoyer (Properties [2000], 4.2) | |
| A reaction: Swoyer says that the explanation is that measurement aims at objective properties, the same in each of these areas. Quite good. |
| 10399 | If a property such as self-identity can only be in one thing, it can't be a universal [Swoyer] |
| Full Idea: Some properties may not be universals, if they can only be exemplified by one thing, such as 'being identical with Socrates'. | |
| From: Chris Swoyer (Properties [2000]) | |
| A reaction: I think it is absurd to think that self-identity is an intrinsic 'property', possessed by everything. That a=a is a convenience for logicians, meaning nothing in the world. And it is relational. The sharing of properties is indeed what needs explanation. |
| 10416 | Can properties have parts? [Swoyer] |
| Full Idea: Can properties have parts? | |
| From: Chris Swoyer (Properties [2000], 6.4) | |
| A reaction: If powers are more fundamental than properties, with the latter often being complexes of the underlying powers, then yes they do. But powers don't. Presumably whatever is fundamental shouldn't have parts. Why? |
| 10417 | There are only first-order properties ('red'), and none of higher-order ('coloured') [Swoyer] |
| Full Idea: 'Elementarism' is the view that there are first-order properties, but that there are no properties of any higher-order. There are first-order properties like various shades of red, but there is no higher-order property, like 'being a colour'. | |
| From: Chris Swoyer (Properties [2000], 7.1) | |
| A reaction: [He cites Bergmann 1968] Interesting. Presumably the programme is naturalistic (and hence congenial to me), and generalisations about properties are conceptual, while the properties themselves are natural. |
| 10413 | The best-known candidate for an identity condition for properties is necessary coextensiveness [Swoyer] |
| Full Idea: The best-known candidate for an identity condition for properties is necessary coextensiveness. | |
| From: Chris Swoyer (Properties [2000], 6) | |
| A reaction: The necessity (in all possible worlds) covers renates and cordates. It is hard to see how one could assert the necessity without some deeper explanation. What makes us deny that actually coextensive renates and cordates have different properties? |
| 10402 | Various attempts are made to evade universals being wholly present in different places [Swoyer] |
| Full Idea: The worry that a single thing could be wholly present in widely separated locations has led to trope theory, to the claim that properties are not located in their instances, or to the view that this treats universals as if they were individuals. | |
| From: Chris Swoyer (Properties [2000], 2.2) | |
| A reaction: I find it dispiriting to come to philosophy in the late twentieth century and have to inherit such a ridiculous view as that there are things that are 'wholly present' in many places. |
| 10400 | Conceptualism says words like 'honesty' refer to concepts, not to properties [Swoyer] |
| Full Idea: Conceptualists urge that words like 'honesty', which might seem to refer to properties, really refer to concepts. A few contemporary philosophers have defended conceptualism, and recent empirical work bears on it, but the view is no longer common. | |
| From: Chris Swoyer (Properties [2000], 1.1) | |
| A reaction: ..and that's all Swoyer says about this very interesting view! He only cites Cocchiarella 1986 Ch.3. The view leaves a lot of work to be done in explaining how nature is, and how our concepts connect to it, and arise in response to it. |
| 10403 | If properties are abstract objects, then their being abstract exemplifies being abstract [Swoyer] |
| Full Idea: If properties are abstract objects, then the property of being abstract should itself exemplify the property of being abstract. | |
| From: Chris Swoyer (Properties [2000], 2.2) | |
| A reaction: Swoyer links this observation with Plato's views on self-predication, and his Third Man Argument (which I bet originated with Aristotle in the Academy!). Do we have a regress of objects, as well as a regress of properties? |
| 10406 | One might hope to reduce possible worlds to properties [Swoyer] |
| Full Idea: One might hope to reduce possible worlds to properties. | |
| From: Chris Swoyer (Properties [2000], 4.1) | |
| A reaction: [He cites Zalta 1983 4.2, and Forrest 1986] I think we are dealing with nothing more than imagined possibilities, which are inferred from our understanding of the underlying 'powers' of the actual world (expressed as 'properties'). |
| 22049 | Transcendental idealism aims to explain objectivity through subjectivity [Bowie] |
| Full Idea: The aim of transcendental idealism is to give a basis for objectivity in terms of subjectivity. | |
| From: Andrew Bowie (German Philosophy: a very short introduction [2010], 1) | |
| A reaction: Hume used subjectivity to undermine the findings of objectivity. There was then no return to naive objectivity. Kant's aim then was to thwart global scepticism. Post-Kantians feared that he had failed. |
| 22055 | The Idealists saw the same unexplained spontaneity in Kant's judgements and choices [Bowie] |
| Full Idea: The Idealist saw in Kant that knowledge, which depends on the spontaneity of judgement, and self-determined spontaneous action, can be seen as sharing the same source, which is not accessible to scientific investigation. | |
| From: Andrew Bowie (German Philosophy: a very short introduction [2010]) | |
| A reaction: This is the 'spontaneity' of judgements and choices which was seen as the main idea in Kant. It inspired romantic individualism. The judgements are the rule-based application of concepts. |
| 22054 | German Idealism tried to stop oppositions of appearances/things and receptivity/spontaneity [Bowie] |
| Full Idea: A central aim of German Idealism is to overcome Kant's oppositions between appearances and thing in themselves, and between receptivity and spontaneity. | |
| From: Andrew Bowie (German Philosophy: a very short introduction [2010], 2) | |
| A reaction: I have the impression that there were two strategies: break down the opposition within the self (Fichte), or break down the opposition in the world (Spinozism). |
| 22056 | Crucial to Idealism is the idea of continuity between receptivity and spontaneous judgement [Bowie] |
| Full Idea: A crucial idea for German Idealism (from Hamann) is that apparently passive receptivity and active spontaneity are in fact different degrees of the same 'activity, and the gap between subject and world can be closed. | |
| From: Andrew Bowie (German Philosophy: a very short introduction [2010], 3) | |
| A reaction: The 'passive' bit seems to be Hume's 'impressions', which are Kant's 'intuitions', which need 'spontaneous' interpretation to become experiences. Critics of Kant said this implied a dualism. |
| 10404 | Extreme empiricists can hardly explain anything [Swoyer] |
| Full Idea: Extreme empiricists wind up unable to explain much of anything. | |
| From: Chris Swoyer (Properties [2000], 2.3) | |
| A reaction: This seems to be the major problem for empiricism, but I am not sure why inference to the best explanation should not be part of a sensible empirical approach. Thinking laws are just 'descriptions of regularities' illustrates the difficulty. |
| 10408 | Intensions are functions which map possible worlds to sets of things denoted by an expression [Swoyer] |
| Full Idea: Intensions are functions that assign a set to the expression at each possible world, ..so the semantic value of 'red' is the function that maps each possible world to the set of things in that world that are red. | |
| From: Chris Swoyer (Properties [2000], 4.2) | |
| A reaction: I am suddenly deeply alienated from this mathematical logicians' way of talking about what 'red' means! We need more psychology, not less. We call things red if we imagine them as looking red. Is imagination a taboo in analytical philosophy? |
| 10409 | Research suggests that concepts rely on typical examples [Swoyer] |
| Full Idea: Recent empirical work on concepts says that many concepts have graded membership, and stress the importance of phenomena like typicality, prototypes, and exemplars. | |
| From: Chris Swoyer (Properties [2000], 4.2) | |
| A reaction: [He cites Rorsch 1978 as the start of this] I say the mind is a database, exactly corresponding to tables, fields etc. Prototypes sound good as the way we identify a given category. Universals are the 'typical' examples labelling areas (e.g. goat). |
| 10401 | The F and G of logic cover a huge range of natural language combinations [Swoyer] |
| Full Idea: All sorts of combinations of copulas ('is') with verbs, adverbs, adjectives, determiners, common nouns, noun phrases and prepositional phrases go over into the familiar Fs and Gs of standard logical notation. | |
| From: Chris Swoyer (Properties [2000], 1.2) | |
| A reaction: This is a nice warning of how misleading logic can be when trying to understand how we think about reality. Montague semantics is an attempt to tackle the problem. Numbers as adjectives are a clear symptom of the difficulties. |
| 10420 | Maybe a proposition is just a property with all its places filled [Swoyer] |
| Full Idea: Some say we can think of a proposition as a limiting case of a property, as when the two-place property '___ loves ___' can become the zero-placed property, or proposition 'that Sam loves Darla'. | |
| From: Chris Swoyer (Properties [2000], 7.6) | |
| A reaction: If you had a prior commitment to the idea that reality largely consists of bundles of properties, I suppose you might find this tempting. |
| 10412 | If laws are mere regularities, they give no grounds for future prediction [Swoyer] |
| Full Idea: If laws were mere regularities, then the fact that observed Fs have been Gs would give us no reason to conclude that those Fs we haven't encountered will also be Gs. | |
| From: Chris Swoyer (Properties [2000], 4.2) | |
| A reaction: I take this simple point to be very powerful. No amount of regularity gives grounds for asserting future patterns - one only has Humean habits. Causal mechanisms are what we are after. |
| 10411 | Two properties can have one power, and one property can have two powers [Swoyer] |
| Full Idea: If properties are identical when they confer the same capacities on their instances, different properties seem able to bestow the same powers (e.g. force), and one property can bestow different powers (attraction or repulsion). | |
| From: Chris Swoyer (Properties [2000], 4.2) | |
| A reaction: Interesting, but possibly a misunderstanding. Powers are basic, and properties are combinations of powers. A 'force' isn't a basic power, it is a consequence of various properties. Relational behaviours are also not basic powers, which are the source. |