30 ideas
12463 | Unlike correspondence, truthmaking can be one truth to many truthmakers, or vice versa [Jacobs] |
Full Idea: I assume a form of truthmaking theory, ..which is a many-many relation, unlike, say correspondence, so that one entity can make multiple truths true and one truth can have multiple truthmakers. | |
From: Jonathan D. Jacobs (A Powers Theory of Modality [2010], §1) | |
A reaction: This sounds like common sense, once you think about it. One tree makes many things true, and one statement about trees is made true by many trees. |
8195 | Undecidable statements result from quantifying over infinites, subjunctive conditionals, and the past tense [Dummett] |
Full Idea: I once wrote that there are three linguistic devices that make it possible for us to frame undecidable statements: quantification over infinity totalities, as expressed by word such as 'never'; the subjunctive conditional form; and the past tense. | |
From: Michael Dummett (Truth and the Past [2001], 4) | |
A reaction: Dummett now repudiates the third one. Statements containing vague concepts also appear to be undecidable. Personally I have no problems with deciding (to a fair extent) about 'never x', and 'if x were true', and 'it was x'. |
8194 | Surely there is no exact single grain that brings a heap into existence [Dummett] |
Full Idea: There is surely no number n such that "n grains of sand do not make a heap, although n+1 grains of sand do" is true. | |
From: Michael Dummett (Truth and the Past [2001], 4) | |
A reaction: It might be argued that there is such a number, but no human being is capable of determing it. Might God know the value of n? On the whole Dummett's view seems the most plausible. |
8190 | Intuitionists rely on the proof of mathematical statements, not their truth [Dummett] |
Full Idea: The intuitionist account of the meaning of mathematical statements does not employ the notion of a statement's being true, but only that of something's being a proof of the statement. | |
From: Michael Dummett (Truth and the Past [2001], 2) | |
A reaction: I remain unconvinced that anyone could give an account of proof that didn't discreetly employ the notion of truth. What are we to make of "we suspect this is true, but no one knows how to prove it?" (e.g. Goldbach's Conjecture). |
8198 | A 'Cambridge Change' is like saying 'the landscape changes as you travel east' [Dummett] |
Full Idea: The idea of 'Cambridge Change' is like saying 'the landscape changes as you travel east'. | |
From: Michael Dummett (Truth and the Past [2001], 5) | |
A reaction: The phrase was coined in Oxford. It is a useful label with which realists can insult solipsists, idealists and other riff-raff. Four Dimensionalists seem to see time in this way. Events sit there, and we travel past them. But there are indexical events. |
8192 | I no longer think what a statement about the past says is just what can justify it [Dummett] |
Full Idea: In distinguishing between what can establish a statement about the past as true and what it is that that statement says, we are repudiating antirealism about the past. | |
From: Michael Dummett (Truth and the Past [2001], 3) | |
A reaction: This is a late shift of ground from the champion of antirealism. If Dummett's whole position is based on a 'justificationist' theory of meaning, he must surely have a different theory of meaning now for statements about the past? |
14375 | If structures result from intrinsic natures of properties, the 'relations' between them can drop out [Jacobs] |
Full Idea: If a relation holds between two properties as a result of their intrinsic natures, then it appears the relation between the properties is not needed to do the structuring of reality; the properties themselves suffice to fix the structure. | |
From: Jonathan D. Jacobs (A Powers Theory of Modality [2010], §4.1) | |
A reaction: [the first bit quotes Jubien 2007] He cites a group of scientific essentialists as spokesmen for this view. Sounds right to me. No on seems able to pin down what a relation is - which may be because there is no such entity. |
14378 | Science aims at identifying the structure and nature of the powers that exist [Jacobs] |
Full Idea: Scientific practice seems aimed precisely at identifying the structure and nature of the powers that exist. | |
From: Jonathan D. Jacobs (A Powers Theory of Modality [2010], §4.3) | |
A reaction: Good. Friends of powers should look at this nice paper by Jacobs. There is a good degree of support for this view from pronouncements of modern scientists. If scientists don't support it, they should. Otherwise they are trapped in the superficial. |
12467 | Powers come from concrete particulars, not from the laws of nature [Jacobs] |
Full Idea: The source of powers is not the laws of nature; it is the powerful nature of the ordinary properties of concrete particulars. | |
From: Jonathan D. Jacobs (A Powers Theory of Modality [2010], §4.2) | |
A reaction: This pithily summarises my own view. People who think the powers of the world derive from the laws either have an implicit religious framework, or they are giving no thought at all to the ontological status of the laws. |
14377 | Possibilities are manifestations of some power, and impossibilies rest on no powers [Jacobs] |
Full Idea: To be possible is just to be one of the many manifestations of some power, and to be impossible is to be a manifestation of no power. | |
From: Jonathan D. Jacobs (A Powers Theory of Modality [2010], §4.2.1) | |
A reaction: [This remark occurs in a discussion of theistic Aristotelianism] I like this. If we say that something is possible, the correct question is to ask what power could bring it about. |
14376 | States of affairs are only possible if some substance could initiate a causal chain to get there [Jacobs] |
Full Idea: A non-actual state of affairs in possible if there actually was a substance capable of initiating a causal chain, perhaps non-deterministic, that could lead to the state of affairs that we claim is possible. | |
From: Jonathan D. Jacobs (A Powers Theory of Modality [2010], §4.2) | |
A reaction: [He is quoting A.R. Pruss 2002] That seems exactly right. Of course the initial substance(s) might create a further substance, such as a transuranic element, which then produces the state of affairs. I favour this strongly actualist view. |
14379 | Counterfactuals invite us to consider the powers picked out by the antecedent [Jacobs] |
Full Idea: A counterfactual is an invitation to consider what the properties picked out by the antecedent are powers for (where Lewis 1973 took it to be an invitation to consider what goes on in a selected possible world). | |
From: Jonathan D. Jacobs (A Powers Theory of Modality [2010], §4.4.3) | |
A reaction: A beautifully simple proposal from Jacobs, with which I agree. This seems to be an expansion of the Ramsey test for conditionals, where you consider the antecedent being true, and see what follows. What, we ask Ramsey, would make it follow? |
14372 | Possible worlds are just not suitable truthmakers for modality [Jacobs] |
Full Idea: Possible worlds are just not the sorts of things that could ground modality; they are not suitable truthmakers. | |
From: Jonathan D. Jacobs (A Powers Theory of Modality [2010], §3) | |
A reaction: Are possible world theorists actually claiming that the worlds 'ground' modality? Maybe Lewis is, since all those concrete worlds had better do some hard work, but for the ersatzist they just provide a kind of formal semantics, leaving ontology to others. |
12466 | All modality is in the properties and relations of the actual world [Jacobs] |
Full Idea: Properties and the relations between them introduce modal connections in the actual world. ..This is a strong form of actualism, since all of modality is part of the fundamental fabric of the actual world. | |
From: Jonathan D. Jacobs (A Powers Theory of Modality [2010], §4) | |
A reaction: This is the view of modality which I find most congenial, with the notion of 'powers' giving us the conceptual framework on which to build an account. |
14371 | We can base counterfactuals on powers, not possible worlds, and hence define necessity [Jacobs] |
Full Idea: Together with a definition of possibility and necessity in terms of counterfactuals, the powers semantics of counterfactuals generates a semantics for modality that appeals to causal powers and not possible worlds. | |
From: Jonathan D. Jacobs (A Powers Theory of Modality [2010], §1) | |
A reaction: Wonderful. Just what the doctor ordered. The only caveat is that if we say that reality is built up from fundamental powers, then might those powers change their character without losing their identity (e.g. gravity getting weaker)? |
12465 | Concrete worlds, unlike fictions, at least offer evidence of how the actual world could be [Jacobs] |
Full Idea: Lewis's concrete worlds give a better account of modality (than fictional worlds). When I learn that a man like me drives a truck, I gain evidence for the fact that I can drive a truck. | |
From: Jonathan D. Jacobs (A Powers Theory of Modality [2010], §3) | |
A reaction: Cf. Idea 12464. Jacobs still rightly rejects this as an account of possibility, since the possibility that I might drive a truck must be rooted in me, not in some other person who drives a truck, even if that person is very like me. |
12464 | If some book described a possibe life for you, that isn't what makes such a life possible [Jacobs] |
Full Idea: Suppose somewhere deep in the rain forest is a book that includes a story about you as a truck-driver. I doubt that you would be inclined the think that that story, that book, is the reason you could have been a truck driver. | |
From: Jonathan D. Jacobs (A Powers Theory of Modality [2010], §3) | |
A reaction: This begins to look like a totally overwhelming and obvious reason why possible worlds (especially as stories) don't give a good metaphysical account of possibility. They provide a semantic structure for modal reasoning, but that is entirely different. |
12469 | Possible worlds semantics gives little insight into modality [Jacobs] |
Full Idea: If we want our semantics for modality to give us insight into the truthmakers for modality, then possible worlds semantics is inadequate. | |
From: Jonathan D. Jacobs (A Powers Theory of Modality [2010], §4.4) | |
A reaction: [See the other ideas of Jacobs (and Jubien) for this] It is an interesting question whether a semantics for a logic is meant to give us insight into how things really are, or whether it just builds nice models. Satisfaction, or truth? |
8199 | The existence of a universe without sentience or intelligence is an unintelligible fantasy [Dummett] |
Full Idea: The existence of a universe from which sentience was permanently absent is an unintelligible fantasy. What exists is what can be known to exist. What is true is what can be known to be true. Reality is what can be experienced and known. | |
From: Michael Dummett (Truth and the Past [2001], 5) | |
A reaction: This strikes me as nonsense. The fact that we cannot think about a universe without introducing a viewpoint does not mean that we cannot 'intellectually imagine' its existence devoid of viewpoints. Nothing could ever experience a star's interior. |
12608 | Concepts are distinguished by roles in judgement, and are thus tied to rationality [Peacocke] |
Full Idea: 'Concept' is a notion tied, in the classical Fregean manner, to cognitive significance. Concepts are distinct if we can judge rationally of one, without the other. Concepts are constitutively and definitionally tied to rationality in this way. | |
From: Christopher Peacocke (Truly Understood [2008], 2.2) | |
A reaction: It seems to a bit optimistic to say, more or less, that thinking is impossible if it isn't rational. Rational beings have been selected for. As Quine nicely observed, duffers at induction have all been weeded out - but they may have existed, briefly. |
12605 | A sense is individuated by the conditions for reference [Peacocke] |
Full Idea: My basic Fregean idea is that a sense is individuated by the fundamental condition for something to be its reference. | |
From: Christopher Peacocke (Truly Understood [2008], Intro) | |
A reaction: For something to actually be its reference (as opposed to imagined reference), truth must be involved. This needs the post-1891 Frege view of such things, and not just the view of concepts as functions which he started with. |
12607 | Fregean concepts have their essence fixed by reference-conditions [Peacocke] |
Full Idea: The Fregean view is that the essence of a concept is given by the fundamental condition for something to be its reference. | |
From: Christopher Peacocke (Truly Understood [2008], 2.1) | |
A reaction: Peacocke is a supporter of the Fregean view. How does this work for concepts of odd creatures in a fantasy novel? Or for mistaken or confused concepts? For Burge's 'arthritis in my thigh'? I don't reject the Fregean view. |
12609 | Concepts have distinctive reasons and norms [Peacocke] |
Full Idea: For each concept, there will be some reasons or norms distinctive of that concept. | |
From: Christopher Peacocke (Truly Understood [2008], 2.3) | |
A reaction: This is Peacocke's bold Fregean thesis (and it sounds rather Kantian to me). I dislike the word 'norms' (long story), but reasons are interesting. The trouble is the distinction between being a reason for something (its cause) and being a reason for me. |
12604 | Any explanation of a concept must involve reference and truth [Peacocke] |
Full Idea: For some particular concept, we can argue that some of its distinctive features are adequately explained only by a possession-condition that involves reference and truth essentially. | |
From: Christopher Peacocke (Truly Understood [2008], Intro) | |
A reaction: He reached this view via the earlier assertion that it is the role in judgement which key to understanding concepts. I like any view of such things which says that truth plays a role. |
8193 | Verification is not an individual but a collective activity [Dummett] |
Full Idea: Verification is not an individual but a collective activity. | |
From: Michael Dummett (Truth and the Past [2001], 3) | |
A reaction: This generates problems. Are deceased members of the community included? (Yes, says Dummett). If someone speaks to angels (Blake!), do they get included? Is a majority necessary? What of weird loners? Etc. |
12610 | Encountering novel sentences shows conclusively that meaning must be compositional [Peacocke] |
Full Idea: The phenomenon of understanding sentences one has never encountered before is decisive against theories of meaning which do not proceed compositionally. | |
From: Christopher Peacocke (Truly Understood [2008], 4.3) | |
A reaction: I agree entirely. It seems obvious, as soon as you begin to slowly construct a long and unusual sentence, and follow the mental processes of the listener. |
8189 | Truth-condition theorists must argue use can only be described by appeal to conditions of truth [Dummett] |
Full Idea: To demonstrate the necessity of a truth-conditional theory of meaning, a proponent of such a theory must argue that use cannot be described without appeal to the conditions for the truth of statements. | |
From: Michael Dummett (Truth and the Past [2001], 1) | |
A reaction: Unlike Dummett, I find that argument rather appealing. How do you decide the possible or appropriate use for a piece of language, if you don't already know what it means. Basing it all on social conventions means it could be meaningless ritual. |
8191 | The truth-conditions theory must get agreement on a conception of truth [Dummett] |
Full Idea: It is not enough for the truth-condition theorist to argue that we need the concept of truth: he must show that we should have the same conception of truth that he has. | |
From: Michael Dummett (Truth and the Past [2001], 2) | |
A reaction: Davidson invites us to accept Tarski's account of truth. It invites the question of what the theory would be like with a very robust correspondence account of truth, or a flabby rather subjective coherence view, or the worst sort of pragmatic view. |
8197 | Maybe past (which affects us) and future (which we can affect) are both real [Dummett] |
Full Idea: Maybe both the past and the future are real, determined by our current temporal perspective. Past is then events capable of having a causal influence upon events near us, and future is events we can affect, but from which we receive no information. | |
From: Michael Dummett (Truth and the Past [2001], 5) | |
A reaction: This is the Four-Dimensional view, which is opposed to Presentism. Might immediate unease is that it gives encouragement to fortune-tellers, whom I have always dismissed with 'You can't see the future, because it doesn't exist'. |
8196 | The present cannot exist alone as a mere boundary; past and future truths are rendered meaningless [Dummett] |
Full Idea: The idea that only the present is real cannot be sustained. St Augustine pointed out that the present has no duration; it is a mere boundary between past and future, and dependent on them. It also denies truth-value to statements about past or future. | |
From: Michael Dummett (Truth and the Past [2001], 5) | |
A reaction: To defend Presentism, I suspect that one must focus entirely on the activities of consciousness and short-term memory. All truths, of past or future, must refer totally to such mental events. But what could an event be if there is no enduring time? |