20 ideas
| 9208 | Philosophers with a new concept are like children with a new toy [Fine,K] |
| Full Idea: Philosophers with a new concept are like children with a new toy; their world shrinks to one in which it takes centre stage. | |
| From: Kit Fine (Intro to 'Modality and Tense' [2005], p.10) | |
| A reaction: A wonderfully accurate observation, I'm afraid. You can trace the entire history of the subject as a wave of obsessions with exciting new ideas. Fine is referring to a posteriori necessities and possible worlds. |
| 14085 | 'Deductivist' structuralism is just theories, with no commitment to objects, or modality [Linnebo] |
| Full Idea: The 'deductivist' version of eliminativist structuralism avoids ontological commitments to mathematical objects, and to modal vocabulary. Mathematics is formulations of various (mostly categorical) theories to describe kinds of concrete structures. | |
| From: Øystein Linnebo (Structuralism and the Notion of Dependence [2008], 1) | |
| A reaction: 'Concrete' is ambiguous here, as mathematicians use it for the actual working maths, as opposed to the metamathematics. Presumably the structures are postulated rather than described. He cites Russell 1903 and Putnam. It is nominalist. |
| 14084 | Non-eliminative structuralism treats mathematical objects as positions in real abstract structures [Linnebo] |
| Full Idea: The 'non-eliminative' version of mathematical structuralism takes it to be a fundamental insight that mathematical objects are really just positions in abstract mathematical structures. | |
| From: Øystein Linnebo (Structuralism and the Notion of Dependence [2008], I) | |
| A reaction: The point here is that it is non-eliminativist because it is committed to the existence of mathematical structures. I oppose this view, since once you are committed to the structures, you may as well admit a vast implausible menagerie of abstracta. |
| 14086 | 'Modal' structuralism studies all possible concrete models for various mathematical theories [Linnebo] |
| Full Idea: The 'modal' version of eliminativist structuralism lifts the deductivist ban on modal notions. It studies what necessarily holds in all concrete models which are possible for various theories. | |
| From: Øystein Linnebo (Structuralism and the Notion of Dependence [2008], I) | |
| A reaction: [He cites Putnam 1967, and Hellman 1989] If mathematical truths are held to be necessary (which seems to be right), then it seems reasonable to include modal notions, about what is possible, in its study. |
| 14087 | 'Set-theoretic' structuralism treats mathematics as various structures realised among the sets [Linnebo] |
| Full Idea: 'Set-theoretic' structuralism rejects deductive nominalism in favour of a background theory of sets, and mathematics as the various structures realized among the sets. This is often what mathematicians have in mind when they talk about structuralism. | |
| From: Øystein Linnebo (Structuralism and the Notion of Dependence [2008], I) | |
| A reaction: This is the big shift from 'mathematics can largely be described in set theory' to 'mathematics just is set theory'. If it just is set theory, then which version of set theory? Which axioms? The safe iterative conception, or something bolder? |
| 14089 | Structuralism differs from traditional Platonism, because the objects depend ontologically on their structure [Linnebo] |
| Full Idea: Structuralism can be distinguished from traditional Platonism in that it denies that mathematical objects from the same structure are ontologically independent of one another | |
| From: Øystein Linnebo (Structuralism and the Notion of Dependence [2008], III) | |
| A reaction: My instincts strongly cry out against all versions of this. If you are going to be a platonist (rather as if you are going to be religious) you might as well go for it big time and have independent objects, which will then dictate a structure. |
| 14083 | Structuralism is right about algebra, but wrong about sets [Linnebo] |
| Full Idea: Against extreme views that all mathematical objects depend on the structures to which they belong, or that none do, I defend a compromise view, that structuralists are right about algebraic objects (roughly), but anti-structuralists are right about sets. | |
| From: Øystein Linnebo (Structuralism and the Notion of Dependence [2008], Intro) |
| 14090 | In mathematical structuralism the small depends on the large, which is the opposite of physical structures [Linnebo] |
| Full Idea: If objects depend on the other objects, this would mean an 'upward' dependence, in that they depend on the structure to which they belong, where the physical realm has a 'downward' dependence, with structures depending on their constituents. | |
| From: Øystein Linnebo (Structuralism and the Notion of Dependence [2008], III) | |
| A reaction: This nicely captures an intuition I have that there is something wrong with a commitment primarily to 'structures'. Our only conception of such things is as built up out of components. Not that I am committing to mathematical 'components'! |
| 14091 | There may be a one-way direction of dependence among sets, and among natural numbers [Linnebo] |
| Full Idea: We can give an exhaustive account of the identity of the empty set and its singleton without mentioning infinite sets, and it might be possible to defend the view that one natural number depends on its predecessor but not vice versa. | |
| From: Øystein Linnebo (Structuralism and the Notion of Dependence [2008], V) | |
| A reaction: Linnebo uses this as one argument against mathematical structuralism, where the small seems to depend on the large. The view of sets rests on the iterative conception, where each level is derived from a lower level. He dismisses structuralism of sets. |
| 9210 | Possible objects are abstract; actual concrete objects are possible; so abstract/concrete are compatible [Fine,K] |
| Full Idea: If it is in the nature of a possible object to be abstract, this is presumably a property it has in any possible circumstance in which it is actual. If it is actual it is also concrete. So the property of being abstract and concrete are not incompatible. | |
| From: Kit Fine (Intro to 'Modality and Tense' [2005], p.14) | |
| A reaction: A rather startling and powerful idea. What of the definition of an abstract object as one which is not in space-time, and lacks causal powers? Could it be that abstraction is a projection of our minds, onto concepts or objects? |
| 9211 | A non-standard realism, with no privileged standpoint, might challenge its absoluteness or coherence [Fine,K] |
| Full Idea: By challenging the assumption that reality is 'absolute' (not relative to a standpoint), or that reality is 'coherent' (it is of a piece, from one standpoint), one accepts worldly facts without a privilege standpoint. I call this 'non-standard' realism. | |
| From: Kit Fine (Intro to 'Modality and Tense' [2005], p.15) | |
| A reaction: Fine's essay 'Tense and Reality' explores his proposal. I'm not drawn to either of his challenges. I have always taken as articles of faith that there could be a God's Eye view of all of reality, and that everything coheres, independent of our view. |
| 14088 | An 'intrinsic' property is either found in every duplicate, or exists independent of all externals [Linnebo] |
| Full Idea: There are two main ways of spelling out an 'intrinsic' property: if and only if it is shared by every duplicate of an object, ...and if and only if the object would have this property even if the rest of the universe were removed or disregarded. | |
| From: Øystein Linnebo (Structuralism and the Notion of Dependence [2008], II) | |
| A reaction: [He cites B.Weatherson's Stanford Encyclopaedia article] How about an intrinsic property being one which explains its identity, or behaviour, or persistence conditions? |
| 9202 | Objects, as well as sentences, can have logical form [Fine,K] |
| Full Idea: We normally think of logical form as exclusively an attribute of sentences; however, the notion may also be taken to have application to objects. | |
| From: Kit Fine (Intro to 'Modality and Tense' [2005], p. 3) | |
| A reaction: A striking proposal which seems intuitively right. If one said that objects have 'powers', one might subsume abstract and physical objects under a single account. |
| 9206 | We must distinguish between the identity or essence of an object, and its necessary features [Fine,K] |
| Full Idea: The failure to distinguish between the identity or essence of an object and its necessary features is an instance of what we may call 'modal mania'. | |
| From: Kit Fine (Intro to 'Modality and Tense' [2005], p. 9) | |
| A reaction: He blames Kripke's work for modal mania, a reaction to Quine's 'contempt' for modal notions. I don't actually understand Fine's remark (yet), but it strikes me as incredibly important! Explanations by email, please. |
| 9205 | The three basic types of necessity are metaphysical, natural and normative [Fine,K] |
| Full Idea: There are three basic forms of necessity - the metaphysical (sourced in the identity of objects); natural necessity (in the 'fabric' of the universe); and normative necessity (in the realm of norms and values). | |
| From: Kit Fine (Intro to 'Modality and Tense' [2005], p. 7) | |
| A reaction: Earlier he has allowed, as less 'basic', logical necessity (in logical forms), and analytic necessity (in meaning). Fine insists that the three kinds should be kept separate (so no metaphysical necessities about nature). I resent this. |
| 9209 | Metaphysical necessity may be 'whatever the circumstance', or 'regardless of circumstances' [Fine,K] |
| Full Idea: There are two fundamental ways in which a property may be metaphysically necessary: it may be a worldly necessity, true whatever the circumstances; or it may be a transcendent necessity, true regardless of the circumstances. | |
| From: Kit Fine (Intro to 'Modality and Tense' [2005], p.10) | |
| A reaction: [See Fine's 'Necessity and Non-Existence' for further details] The distinction seems to be that the first sort needs some circumstances (e.g. a physical world?), whereas the second sort doesn't (logical relations?). He also applies it to existence. |
| 9200 | Empiricists suspect modal notions: either it happens or it doesn't; it is just regularities. [Fine,K] |
| Full Idea: Empiricists have always been suspicious of modal notions: the world is an on-or-off matter - either something happens or it does not. ..Empiricists, in so far as they have been able to make sense of modality, have tended to see it as a form of regularity. | |
| From: Kit Fine (Intro to 'Modality and Tense' [2005], p. 1) | |
| A reaction: Fine is discussing the two extreme views of Quine and Lewis. It is one thing to have views about what is possible, and another to include possibilities 'in your ontology'. Our imagination competes with our extrapolations from actuality. |
| 9207 | If sentence content is all worlds where it is true, all necessary truths have the same content! [Fine,K] |
| Full Idea: The content of a sentence is often identified with the set of possible worlds in which it is true, where the worlds are metaphysically possible. But this has the awkward consequence that all metaphysically necessary truths will have the same content. | |
| From: Kit Fine (Intro to 'Modality and Tense' [2005], p.10) | |
| A reaction: I've never understood how the content of a sentence could be a vast set of worlds, so I am delighted to see this proposal be torpedoed. That doesn't mean that truth conditions across possible worlds is not a promising notion. |
| 1748 | Archelaus was the first person to say that the universe is boundless [Archelaus, by Diog. Laertius] |
| Full Idea: Archelaus was the first person to say that the universe is boundless. | |
| From: report of Archelaus (fragments/reports [c.450 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 02.Ar.3 |
| 5989 | Archelaus said life began in a primeval slime [Archelaus, by Schofield] |
| Full Idea: Archelaus wrote that life on Earth began in a primeval slime. | |
| From: report of Archelaus (fragments/reports [c.450 BCE]) by Malcolm Schofield - Archelaus | |
| A reaction: This sounds like a fairly clearcut assertion of the production of life by evolution. Darwin's contribution was to propose the mechanism for achieving it. We should honour the name of Archelaus for this idea. |