22 ideas
17713 | After 1903, Husserl avoids metaphysical commitments [Mares] |
Full Idea: In Husserl's philosophy after 1903, he is unwilling to commit himself to any specific metaphysical views. | |
From: Edwin D. Mares (A Priori [2011], 08.2) |
9967 | 'Impure' sets have a concrete member, while 'pure' (abstract) sets do not [Jubien] |
Full Idea: Any set with a concrete member is 'impure'. 'Pure' sets are those that are not impure, and are paradigm cases of abstract entities, such as the sort of sets apparently dealt with in Zermelo-Fraenkel (ZF) set theory. | |
From: Michael Jubien (Ontology and Mathematical Truth [1977], p.116) | |
A reaction: [I am unclear whether Jubien is introducing this distinction] This seems crucial in accounts of mathematics. On the one had arithmetic can be built from Millian pebbles, giving impure sets, while logicists build it from pure sets. |
9968 | A model is 'fundamental' if it contains only concrete entities [Jubien] |
Full Idea: A first-order model can be viewed as a kind of ordered set, and if the domain of the model contains only concrete entities then it is a 'fundamental' model. | |
From: Michael Jubien (Ontology and Mathematical Truth [1977], p.117) | |
A reaction: An important idea. Fundamental models are where the world of logic connects with the physical world. Any account of relationship between fundamental models and more abstract ones tells us how thought links to world. |
9965 | There couldn't just be one number, such as 17 [Jubien] |
Full Idea: It makes no sense to suppose there might be just one natural number, say seventeen. | |
From: Michael Jubien (Ontology and Mathematical Truth [1977], p.113) | |
A reaction: Hm. Not convinced. If numbers are essentially patterns, we might only have the number 'twelve', because we had built our religion around anything which exhibited that form (in any of its various arrangements). Nice point, though. |
17715 | The truth of the axioms doesn't matter for pure mathematics, but it does for applied [Mares] |
Full Idea: The epistemological burden of showing that the axioms are true is removed if we are only studying pure mathematics. If, however, we want to look at applied mathematics, then this burden returns. | |
From: Edwin D. Mares (A Priori [2011], 11.4) | |
A reaction: One of those really simple ideas that hits the spot. Nice. The most advanced applied mathematics must rest on counting and measuring. |
9966 | The subject-matter of (pure) mathematics is abstract structure [Jubien] |
Full Idea: The subject-matter of (pure) mathematics is abstract structure per se. | |
From: Michael Jubien (Ontology and Mathematical Truth [1977], p.115) | |
A reaction: This is the Structuralist idea beginning to take shape after Benacerraf's launching of it. Note that Jubien gets there by his rejection of platonism, whereas some structuralist have given a platonist interpretation of structure. |
9963 | If we all intuited mathematical objects, platonism would be agreed [Jubien] |
Full Idea: If the intuition of mathematical objects were general, there would be no real debate over platonism. | |
From: Michael Jubien (Ontology and Mathematical Truth [1977], p.111) | |
A reaction: It is particularly perplexing when Gödel says that his perception of them is just like sight or smell, since I have no such perception. How do you individuate very large numbers, or irrational numbers, apart from writing down numerals? |
9962 | How can pure abstract entities give models to serve as interpretations? [Jubien] |
Full Idea: I am unable to see how the mere existence of pure abstract entities enables us to concoct appropriate models to serve as interpretations. | |
From: Michael Jubien (Ontology and Mathematical Truth [1977], p.111) | |
A reaction: Nice question. It is always assumed that once we have platonic realm, that everything else follows. Even if we are able to grasp the objects, despite their causal inertness, we still have to discern innumerable relations between them. |
9964 | Since mathematical objects are essentially relational, they can't be picked out on their own [Jubien] |
Full Idea: The essential properties of mathematical entities seem to be relational, ...so we make no progress unless we can pick out some mathematical entities wihout presupposing other entities already picked out. | |
From: Michael Jubien (Ontology and Mathematical Truth [1977], p.112) | |
A reaction: [compressed] Jubien is a good critic of platonism. He has identified the problem with Frege's metaphor of a 'borehole', where we discover delightful new properties of numbers simply by reaching them. |
17716 | Mathematics is relations between properties we abstract from experience [Mares] |
Full Idea: Aristotelians treat mathematical facts as relations between properties. These properties, moreover, are abstracted from our experience of things. ...This view finds a natural companion in structuralism. | |
From: Edwin D. Mares (A Priori [2011], 11.7) | |
A reaction: This is the view of mathematics that I personally favour. The view that we abstract 'five' from a group of five pebbles is too simplistic, but this is the right general approach. |
9969 | The empty set is the purest abstract object [Jubien] |
Full Idea: The empty set is the pure abstract object par excellence. | |
From: Michael Jubien (Ontology and Mathematical Truth [1977], p.118 n8) | |
A reaction: So a really good PhD on the empty set could crack the whole nature of reality. Get to work, whoever you are! |
17703 | Light in straight lines is contingent a priori; stipulated as straight, because they happen to be so [Mares] |
Full Idea: It seems natural to claim that light rays moving in straight lines is contingent but a priori. Scientists stipulate that they are the standard by which we measure straightness, but their appropriateness for this task is a contingent feature of the world. | |
From: Edwin D. Mares (A Priori [2011], 02.9) | |
A reaction: This resembles the metre rule in Paris. It is contingent that something is a certain way, so we make being that way a conventional truth, which can therefore be known via the convention, rather than via the contingent fact. |
17714 | Aristotelians dislike the idea of a priori judgements from pure reason [Mares] |
Full Idea: Aristotelians tend to eschew talk about a special faculty of pure reason that is responsible for all of our a priori judgements. | |
From: Edwin D. Mares (A Priori [2011], 08.9) | |
A reaction: He is invoking Carrie Jenkins's idea that the a priori is knowledge of relations between concepts which have been derived from experience. Nice idea. We thus have an empirical a priori, integrated into the natural world. Abstraction must be involved. |
17705 | Empiricists say rationalists mistake imaginative powers for modal insights [Mares] |
Full Idea: Empiricist critiques of rationalism often accuse rationalists of confusing the limits of their imaginations with real insight into what is necessarily true. | |
From: Edwin D. Mares (A Priori [2011], 03.01) | |
A reaction: See ideas on 'Conceivable as possible' for more on this. You shouldn't just claim to 'see' that something is true, but be willing to offer some sort of reason, truthmaker or grounding. Without that, you may be right, but you are on weak ground. |
17700 | The most popular view is that coherent beliefs explain one another [Mares] |
Full Idea: In what is perhaps the most popular version of coherentism, a system of beliefs is a set of beliefs that explain one another. | |
From: Edwin D. Mares (A Priori [2011], 01.5) | |
A reaction: These seems too simple. My first response would be that explanations are what result from coherence sets of beliefs. I may have beliefs that explain nothing, but at least have the virtue of being coherent. |
17704 | Operationalism defines concepts by our ways of measuring them [Mares] |
Full Idea: The central claim of Percy Bridgman's theory of operational definitions (1920s), is that definitions of certain scientific concepts are given by the ways that we have to measure them. For example, a straight line is 'the path of a light ray'. | |
From: Edwin D. Mares (A Priori [2011], 02.9) | |
A reaction: It is often observed that this captures the spirit of Special Relativity. |
17710 | Aristotelian justification uses concepts abstracted from experience [Mares] |
Full Idea: Aristotelian justification is the process of reasoning using concepts that are abstracted from experience (rather than, say, concepts that are innate or those that we associate with the meanings of words). | |
From: Edwin D. Mares (A Priori [2011], 08.1) | |
A reaction: See Carrie Jenkins for a full theory along these lines (though she doesn't mention Aristotle). This is definitely my preferred view of concepts. |
17706 | The essence of a concept is either its definition or its conceptual relations? [Mares] |
Full Idea: In the 'classical theory' a concept includes in it those concepts that define it. ...In the 'theory theory' view the content of a concept is determined by its relationship to other concepts. | |
From: Edwin D. Mares (A Priori [2011], 03.10) | |
A reaction: Neither of these seem to give an intrinsic account of a concept, or any account of how the whole business gets off the ground. |
17701 | Possible worlds semantics has a nice compositional account of modal statements [Mares] |
Full Idea: Possible worlds semantics is appealing because it gives a compositional analysis of the truth conditions of statements about necessity and possibility. | |
From: Edwin D. Mares (A Priori [2011], 02.2) | |
A reaction: Not sure I get this. Is the meaning composed by the gradual addition of worlds? If not, how is meaning composed in the normal way, from component words and phrases? |
17702 | Unstructured propositions are sets of possible worlds; structured ones have components [Mares] |
Full Idea: An unstructured proposition is a set of possible worlds. ....Structured propositions contain entities that correspond to various parts of the sentences or thoughts that express them. | |
From: Edwin D. Mares (A Priori [2011], 02.3) | |
A reaction: I am definitely in favour of structured propositions. It strikes me as so obvious as to be not worth discussion - so I am obviously missing something here. Mares says structured propositions are 'more convenient'. |
468 | Musical performance can reveal a range of virtues [Damon of Ath.] |
Full Idea: In singing and playing the lyre, a boy will be likely to reveal not only courage and moderation, but also justice. | |
From: Damon (fragments/reports [c.460 BCE], B4), quoted by (who?) - where? |
17708 | Maybe space has points, but processes always need regions with a size [Mares] |
Full Idea: One theory is that space is made up of dimensionless points, but physical processes cannot take place in regions of less than a certain size. | |
From: Edwin D. Mares (A Priori [2011], 06.7) | |
A reaction: Thinkers in sympathy with verificationism presumably won't like this, and may prefer Feynman's view. |