32 ideas
| 17275 | Realist metaphysics concerns what is real; naive metaphysics concerns natures of things [Fine,K] |
| Full Idea: We may broadly distinguish between two main branches of metaphysics: the 'realist' or 'critical' branch is concerned with what is real (tense, values, numbers); the 'naive' or 'pre-critical' branch concerns natures of things irrespective of reality. | |
| From: Kit Fine (Guide to Ground [2012], 1.02) | |
| A reaction: [compressed] The 'natures' of things are presumably the essences. He cites 3D v 4D objects, and the status of fictional characters, as examples of the second type. Fine says ground is central to realist metaphysics. |
| 17282 | Truths need not always have their source in what exists [Fine,K] |
| Full Idea: There is no reason in principle why the ultimate source of what is true should always lie in what exists. | |
| From: Kit Fine (Guide to Ground [2012], 1.03) | |
| A reaction: This seems to be the weak point of the truthmaker theory, since truths about non-existence are immediately in trouble. Saying reality makes things true is one thing, but picking out a specific bit of it for each truth is not so easy. |
| 17283 | If the truth-making relation is modal, then modal truths will be grounded in anything [Fine,K] |
| Full Idea: The truth-making relation is usually explicated in modal terms, ...but this lets in far too much. Any necessary truth will be grounded by anything. ...The fact that singleton Socrates exists will be a truth-maker for the proposition that Socrates exists. | |
| From: Kit Fine (Guide to Ground [2012], 1.03) | |
| A reaction: If truth-makers are what has to 'exist' for something to be true, then maybe nothing must exist for a necessity to be true - in which case it has no truth maker. Or maybe 2 and 4 must 'exist' for 2+2=4? |
| 14239 | The empty set is usually derived from Separation, but it also seems to need Infinity [Oliver/Smiley] |
| Full Idea: The empty set is usually derived via Zermelo's axiom of separation. But the axiom of separation is conditional: it requires the existence of a set in order to generate others as subsets of it. The original set has to come from the axiom of infinity. | |
| From: Oliver,A/Smiley,T (What are Sets and What are they For? [2006], 1.2) | |
| A reaction: They charge that this leads to circularity, as Infinity depends on the empty set. |
| 14240 | The empty set is something, not nothing! [Oliver/Smiley] |
| Full Idea: Some authors need to be told loud and clear: if there is an empty set, it is something, not nothing. | |
| From: Oliver,A/Smiley,T (What are Sets and What are they For? [2006], 1.2) | |
| A reaction: I'm inclined to think of a null set as a pair of brackets, so maybe that puts it into a metalanguage. |
| 14241 | We don't need the empty set to express non-existence, as there are other ways to do that [Oliver/Smiley] |
| Full Idea: The empty set is said to be useful to express non-existence, but saying 'there are no Us', or ¬∃xUx are no less concise, and certainly less roundabout. | |
| From: Oliver,A/Smiley,T (What are Sets and What are they For? [2006], 1.2) |
| 14242 | Maybe we can treat the empty set symbol as just meaning an empty term [Oliver/Smiley] |
| Full Idea: Suppose we introduce Ω not as a term standing for a supposed empty set, but as a paradigm of an empty term, not standing for anything. | |
| From: Oliver,A/Smiley,T (What are Sets and What are they For? [2006], 1.2) | |
| A reaction: This proposal, which they go on to explore, seems to mean that Ω (i.e. the traditional empty set symbol) is no longer part of set theory but is part of semantics. |
| 14243 | The unit set may be needed to express intersections that leave a single member [Oliver/Smiley] |
| Full Idea: Thomason says with no unit sets we couldn't call {1,2}∩{2,3} a set - but so what? Why shouldn't the intersection be the number 2? However, we then have to distinguish three different cases of intersection (common subset or member, or disjoint). | |
| From: Oliver,A/Smiley,T (What are Sets and What are they For? [2006], 2.2) |
| 17286 | Logical consequence is verification by a possible world within a truth-set [Fine,K] |
| Full Idea: Under the possible worlds semantics for logical consequence, each sentence of a language is associated with a truth-set of possible worlds in which it is true, and then something is a consequence if one of these worlds verifies it. | |
| From: Kit Fine (Guide to Ground [2012], 1.10) | |
| A reaction: [compressed, and translated into English; see Fine for more symbolic version; I'm more at home in English] |
| 14234 | If you only refer to objects one at a time, you need sets in order to refer to a plurality [Oliver/Smiley] |
| Full Idea: A 'singularist', who refers to objects one at a time, must resort to the language of sets in order to replace plural reference to members ('Henry VIII's wives') by singular reference to a set ('the set of Henry VIII's wives'). | |
| From: Oliver,A/Smiley,T (What are Sets and What are they For? [2006], Intro) | |
| A reaction: A simple and illuminating point about the motivation for plural reference. Null sets and singletons give me the creeps, so I would personally prefer to avoid set theory when dealing with ontology. |
| 14237 | We can use plural language to refer to the set theory domain, to avoid calling it a 'set' [Oliver/Smiley] |
| Full Idea: Plurals earn their keep in set theory, to answer Skolem's remark that 'in order to treat of 'sets', we must begin with 'domains' that are constituted in a certain way'. We can speak in the plural of 'the objects', not a 'domain' of objects. | |
| From: Oliver,A/Smiley,T (What are Sets and What are they For? [2006], Intro) | |
| A reaction: [Skolem 1922:291 in van Heijenoort] Zermelo has said that the domain cannot be a set, because every set belongs to it. |
| 14245 | Logical truths are true no matter what exists - but predicate calculus insists that something exists [Oliver/Smiley] |
| Full Idea: Logical truths should be true no matter what exists, so true even if nothing exists. The classical predicate calculus, however, makes it logically true that something exists. | |
| From: Oliver,A/Smiley,T (What are Sets and What are they For? [2006], 5.1) |
| 14246 | If mathematics purely concerned mathematical objects, there would be no applied mathematics [Oliver/Smiley] |
| Full Idea: If mathematics was purely concerned with mathematical objects, there would be no room for applied mathematics. | |
| From: Oliver,A/Smiley,T (What are Sets and What are they For? [2006], 5.1) | |
| A reaction: Love it! Of course, they are using 'objects' in the rather Fregean sense of genuine abstract entities. I don't see why fictionalism shouldn't allow maths to be wholly 'pure', although we have invented fictions which actually have application. |
| 14247 | Sets might either represent the numbers, or be the numbers, or replace the numbers [Oliver/Smiley] |
| Full Idea: Identifying numbers with sets may mean one of three quite different things: 1) the sets represent the numbers, or ii) they are the numbers, or iii) they replace the numbers. | |
| From: Oliver,A/Smiley,T (What are Sets and What are they For? [2006], 5.2) | |
| A reaction: Option one sounds the most plausible to me. I will take numbers to be patterns embedded in nature, and sets are one way of presenting them in shorthand form, in order to bring out what is repeated. |
| 17272 | 2+2=4 is necessary if it is snowing, but not true in virtue of the fact that it is snowing [Fine,K] |
| Full Idea: It is necessary that if it is snowing then 2+2=4, but the fact that 2+2=4 does not obtain in virtue of the fact that it is snowing. | |
| From: Kit Fine (Guide to Ground [2012], 1.01) | |
| A reaction: Critics dislike 'in virtue of' (as vacuous), but I can't see how you can disagree with this obvervation of Fine's. You can hardly eliminate the word 'because' from English, or say p is because of some object. We demand the right to keep asking 'why?'! |
| 17276 | If you say one thing causes another, that leaves open that the 'other' has its own distinct reality [Fine,K] |
| Full Idea: It will not do to say that the physical is causally determinative of the mental, since that leaves open the possibility that the mental has a distinct reality over and above that of the physical. | |
| From: Kit Fine (Guide to Ground [2012], 1.02) | |
| A reaction: The context is a defence of grounding, so that if we say the mind is 'grounded' in the brain, we are saying rather more than merely that it is caused by the brain. A ghost might be 'caused' by a bar of soap. Nice. |
| 17284 | An immediate ground is the next lower level, which gives the concept of a hierarchy [Fine,K] |
| Full Idea: It is the notion of 'immediate' ground that provides us with our sense of a ground-theoretic hierarchy. For any truth, we can take its immediate grounds to be at the next lower level. | |
| From: Kit Fine (Guide to Ground [2012], 1.05 'Mediate') | |
| A reaction: Are the levels in the reality, the structure or the descriptions? I vote for the structure. I'm defending the idea that 'essence' picks out the bottom of a descriptive level. |
| 17285 | 'Strict' ground moves down the explanations, but 'weak' ground can move sideways [Fine,K] |
| Full Idea: We might think of strict ground as moving us down in the explanatory hierarchy. ...Weak ground, on the other hand, may also move us sideways in the explanatory hierarchy. | |
| From: Kit Fine (Guide to Ground [2012], 1.05 'Weak') | |
| A reaction: This seems to me rather illuminating. For example, is the covering law account of explanation a 'sideways' move in explanation. Are inductive generalities mere 'sideways' accounts. Both fail to dig deeper. |
| 17288 | We learn grounding from what is grounded, not what does the grounding [Fine,K] |
| Full Idea: It is the fact to be grounded that 'points' to its ground and not the grounds that point to what they ground. | |
| From: Kit Fine (Guide to Ground [2012], 1.11) | |
| A reaction: What does the grounding may ground all sorts of other things, but what is grounded only has one 'full' (as opposed to 'partial', in Fine's terminology) ground. He says this leads to a 'top-down' approach to the study of grounds. |
| 17281 | If grounding is a relation it must be between entities of the same type, preferably between facts [Fine,K] |
| Full Idea: In so far as ground is regarded as a relation it should be between entities of the same type, and the entities should probably be taken as worldly entities, such as facts, rather than as representational entities, such as propositions. | |
| From: Kit Fine (Guide to Ground [2012], 1.02) | |
| A reaction: That's more like it (cf. Idea 17280). The consensus of this discussion seems to point to facts as the best relata, for all the vagueness of facts, and the big question of how fine-grained facts should be (and how dependent they are on descriptions). |
| 17280 | Ground is best understood as a sentence operator, rather than a relation between predicates [Fine,K] |
| Full Idea: Ground is perhaps best regarded as an operation (signified by an operator on sentences) rather than as a relation (signified by a predicate) | |
| From: Kit Fine (Guide to Ground [2012], 1.02) | |
| A reaction: Someone in this book (Koslicki?) says this is to avoid metaphysical puzzles over properties. I don't like the idea, because it makes grounding about sentences when it should be about reality. Fine is so twentieth century. Audi rests ground on properties. |
| 17290 | Only metaphysical grounding must be explained by essence [Fine,K] |
| Full Idea: If the grounding relation is not metaphysical (such as normative or natural grounding), there is no need for there to be an explanation of its holding in terms of the essentialist nature of the items involved. | |
| From: Kit Fine (Guide to Ground [2012], 1.11) | |
| A reaction: He accepts that some things have partial grounds in different areas of reality. |
| 17274 | Philosophical explanation is largely by ground (just as cause is used in science) [Fine,K] |
| Full Idea: For philosophers interested in explanation - of what accounts for what - it is largely through the notion of ontological ground that such questions are to be pursued. Ground, if you like, stands to philosophy as cause stands to science. | |
| From: Kit Fine (Guide to Ground [2012], 1.02) | |
| A reaction: Why does the ground have to be 'ontological'? It isn't the existence of the snow that makes me cold, but the fact that I am lying in it. Better to talk of 'factual' ground (or 'determinative' ground), and then causal grounds are a subset of those? |
| 17278 | We can only explain how a reduction is possible if we accept the concept of ground [Fine,K] |
| Full Idea: It is only by embracing the concept of a ground as a metaphysical form of explanation in its own right that one can adequately explain how a reduction of the reality of one thing to another should be understood. | |
| From: Kit Fine (Guide to Ground [2012], 1.02) | |
| A reaction: I love that we are aiming to say 'how' a reduction should be understood, and not just 'that' it exists. I'm not sure about Fine's emphasis on explaining 'realities', when I think we are after more like structural relations or interconnected facts. |
| 17287 | Facts, such as redness and roundness of a ball, can be 'fused' into one fact [Fine,K] |
| Full Idea: Given any facts, there will be a fusion of those facts. Given the facts that the ball is red and that it is round, there is a fused fact that it is 'red and round'. | |
| From: Kit Fine (Guide to Ground [2012], 1.10) | |
| A reaction: This is how we make 'units' for counting. Any type of thing which can be counted can be fused, such as the first five prime numbers, forming the 'first' group for some discussion. Any objects can be fused to make a unit - but is it thereby a 'unity'? |
| 17279 | Even a three-dimensionalist might identify temporal parts, in their thinking [Fine,K] |
| Full Idea: Even the three-dimensionalist might be willing to admit that material things have temporal parts. For given any persisting object, he might suppose that 'in thought' we could mark out its temporal segments or parts. | |
| From: Kit Fine (Guide to Ground [2012], 1.02) | |
| A reaction: A big problem with temporal parts is how thin they are. Hawley says they are as fine-grained as time itself, but what if time has no grain? How thin can you 'think' a temporal part to be? Fine says imagined parts are grounded in things, not vice versa. |
| 17273 | Each basic modality has its 'own' explanatory relation [Fine,K] |
| Full Idea: I am inclined to the view that ....each basic modality should be associated with its 'own' explanatory relation. | |
| From: Kit Fine (Guide to Ground [2012], 1.01) | |
| A reaction: He suggests that 'grounding' connects the various explanatory relations of the different modalities. I like this a lot. Why assert any necessity without some concept of where the necessity arises, and hence where it is grounded? You've got to eat. |
| 17289 | Every necessary truth is grounded in the nature of something [Fine,K] |
| Full Idea: It might be held as a general thesis that every necessary truth is grounded in the nature of certain items. | |
| From: Kit Fine (Guide to Ground [2012], 1.11) | |
| A reaction: [He cites his own 1994 for this] I'm not sure if I can embrace the 'every' in this. I would only say, more cautiously, that I can only make sense of necessity claims when I see their groundings - and I don't take a priori intuition as decent grounding. |
| 17291 | We explain by identity (what it is), or by truth (how things are) [Fine,K] |
| Full Idea: I think it should be recognised that there are two fundamentally different types of explanation; one is of identity, or of what something is; and the other is of truth, or of how things are. | |
| From: Kit Fine (Guide to Ground [2012], 1.11) |
| 17271 | Is there metaphysical explanation (as well as causal), involving a constitutive form of determination? [Fine,K] |
| Full Idea: In addition to scientific or causal explanation, there maybe a distinctive kind of metaphysical explanation, in which explanans and explanandum are connected, not through some causal mechanism, but through some constitutive form of determination. | |
| From: Kit Fine (Guide to Ground [2012], Intro) | |
| A reaction: I'm unclear why determination has to be 'constitutive', since I would take determination to be a family of concepts, with constitution being one of them, as when chess pieces determine a chess set. Skip 'metaphysical'; just have Determinative Explanation. |
| 17277 | If mind supervenes on the physical, it may also explain the physical (and not vice versa) [Fine,K] |
| Full Idea: It is not enough to require that the mental should modally supervene on the physical, since that still leaves open the possibility that the physical is itself ultimately to be understood in terms of the mental. | |
| From: Kit Fine (Guide to Ground [2012], 1.02) | |
| A reaction: See Horgan on supervenience. Supervenience is a question, not an answer. The first question is whether the supervenience is mutual, and if not, which 'direction' does it go in? |
| 8592 | Empty space is measurable in ways in which empty time necessarily is not [Bennett, by Shoemaker] |
| Full Idea: Because of the multidimensionality of space and unidimensionality of time, empty space is measurable in ways in which empty time necessarily is not. | |
| From: report of Jonathan Bennett (Kant's Analytic [1966], p.175) by Sydney Shoemaker - Time Without Change p.49 n4 | |
| A reaction: An interesting observation, which could have been used by Samuel Clarke in his attempts to prove absolute space to Leibniz. The point does not prove absolute space, of course, but it seems to make a difference. |