Combining Texts

All the ideas for 'Contextualist Solutions to Scepticism', 'Mathematics without Numbers' and 'Causation in a Physical World'

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9 ideas

6. Mathematics / B. Foundations for Mathematics / 7. Mathematical Structuralism / c. Nominalist structuralism
Modal structuralism says mathematics studies possible structures, which may or may not be actualised [Hellman, by Friend]
     Full Idea: The modal structuralist thinks of mathematical structures as possibilities. The application of mathematics is just the realisation that a possible structure is actualised. As structures are possibilities, realist ontological problems are avoided.
     From: report of Geoffrey Hellman (Mathematics without Numbers [1989]) by Michèle Friend - Introducing the Philosophy of Mathematics 4.3
     A reaction: Friend criticises this and rejects it, but it is appealing. Mathematics should aim to be applicable to any possible world, and not just the actual one. However, does the actual world 'actualise a mathematical structure'?
Statements of pure mathematics are elliptical for a sort of modal conditional [Hellman, by Chihara]
     Full Idea: Hellman represents statements of pure mathematics as elliptical for modal conditionals of a certain sort.
     From: report of Geoffrey Hellman (Mathematics without Numbers [1989]) by Charles Chihara - A Structural Account of Mathematics 5.3
     A reaction: It's a pity there is such difficulty in understanding conditionals (see Graham Priest on the subject). I intuit a grain of truth in this, though I take maths to reflect the structure of the actual world (with possibilities being part of that world).
Modal structuralism can only judge possibility by 'possible' models [Shapiro on Hellman]
     Full Idea: The usual way to show that a sentence is possible is to show that it has a model, but for Hellman presumably a sentence is possible if it might have a model (or if, possibly, it has a model). It is not clear what this move brings us.
     From: comment on Geoffrey Hellman (Mathematics without Numbers [1989]) by Stewart Shapiro - Philosophy of Mathematics 7.3
     A reaction: I can't assess this, but presumably the possibility of the model must be demonstrated in some way. Aren't all models merely possible, because they are based on axioms, which seem to be no more than possibilities?
13. Knowledge Criteria / C. External Justification / 6. Contextual Justification / a. Contextualism
Contextualism needs a semantics for knowledge sentences that are partly indexical [Schiffer,S]
     Full Idea: Contextualist semantics must capture the 'indexical' nature of knowledge claims, the fact that different utterances of a knowledge sentence with no apparent indexical terms can express different propositions.
     From: Stephen Schiffer (Contextualist Solutions to Scepticism [1996], p.325), quoted by Keith DeRose - The Case for Contextualism 1.5
     A reaction: Schiffer tries to show that this is too difficult, and DeRose defends contextualism against the charge.
The indexical aspect of contextual knowledge might be hidden, or it might be in what 'know' means [Schiffer,S]
     Full Idea: One might have a 'hidden-indexical' theory of knowledge sentences: they contain constituents that are not the semantic values of any terms; ...or 'to know' itself might be indexical, as in 'I know[easy] I have hands' or 'I know[tough] I have hands'.
     From: Stephen Schiffer (Contextualist Solutions to Scepticism [1996], p.326-7), quoted by Keith DeRose - The Case for Contextualism 1.5
     A reaction: [very compressed] Given the choice, I would have thought it was in 'know', since to say 'either you know p or you don't' sounds silly to me.
26. Natural Theory / C. Causation / 1. Causation
Explain single events by general rules, or vice versa, or probability explains both, or they are unconnected [Field,H]
     Full Idea: Some think singular causal claims should be explained in terms of general causal claims; some think the order should be reversed; some think a third thing (e.g. objective probability) will explain both; and some think they are only loosely connected.
     From: Hartry Field (Causation in a Physical World [2003], 2)
     A reaction: I think Ducasse gives the best account, which is the second option, of giving singular causal claims priority. Probability (Mellor) strikes me as a non-starter, and the idea that they are fairly independent seems rather implausible.
26. Natural Theory / C. Causation / 5. Direction of causation
Physical laws are largely time-symmetric, so they make a poor basis for directional causation [Field,H]
     Full Idea: It is sometimes pointed out that (perhaps with a few minor exceptions) the fundamental physical laws are completely time-symmetric. If so, then if one is inclined to found causation on fundamental physical law, it isn't evident how directionality gets in.
     From: Hartry Field (Causation in a Physical World [2003], 1)
     A reaction: All my instincts tell me that causation is more fundamental than laws, and that directionality is there at the start. That, though, raises the nice question of how, if causation explains laws, the direction eventually gets left OUT!
Identifying cause and effect is not just conventional; we explain later events by earlier ones [Field,H]
     Full Idea: It is not just that the earlier member of a cause-effect pair is conventionally called the cause; it is also connected with other temporal asymmetries that play an important role in our practices. We tend to explain later events in terms of earlier ones.
     From: Hartry Field (Causation in a Physical World [2003], 1)
     A reaction: We also interfere with the earlier one to affect the later one, and not vice versa (Idea 8363). I am inclined to think that attempting to explain the direction of causation is either pointless or hopeless.
The only reason for adding the notion of 'cause' to fundamental physics is directionality [Field,H]
     Full Idea: Although it is true that the notion of 'cause' is not needed in fundamental physics, even statistical physics, still directionality considerations don't preclude this notion from being consistently added to fundamental physics.
     From: Hartry Field (Causation in a Physical World [2003], 1)
     A reaction: This only makes sense if the notion of cause already has directionality built into it, which I think is correct. The physicist might reply that they don't care about directionality, but the whole idea of an experiment seems to depend on it (Idea 8363).