display all the ideas for this combination of texts
19 ideas
| 15290 | What reduces the field of the possible is a step towards necessity [Harré/Madden] |
| Full Idea: Whatever reduces the field of the possible is a step towards necessity. | |
| From: Harré,R./Madden,E.H. (Causal Powers [1975], 7.IV) | |
| A reaction: This is a deeply stirring idea, because it suddenly opens up a research project of narrowing the possibilities, with a stunning Holy Grail at the end of it. Sherlock Holmes said this first, of course. |
| 15291 | There is 'absolute' necessity (implied by all propositions) and 'relative' necessity (from what is given) [Harré/Madden] |
| Full Idea: In addition to absolute necessity ('p is strictly implied by ¬p'), i.e. p strictly implied by any proposition whatever, C.I. Lewis also distinguished relative necessity ('p implied by what is given or known'). | |
| From: Harré,R./Madden,E.H. (Causal Powers [1975], 7.V) | |
| A reaction: Once you accept this distinction you find that the 'relative' one comes in all sorts of degrees. You "have to" put more salt in this soup. (Deontic' necessity, someone on Twitter tells me!) |
| 14680 | Logical possibility contains metaphysical possibility, which contains nomological possibility [Salmon,N] |
| Full Idea: Just as nomological possibility is a special kind of metaphysical possibility, so metaphysical possibility is a special kind of logical possibility. | |
| From: Nathan Salmon (The Logic of What Might Have Been [1989], III) | |
| A reaction: This is the standard view of how the three types of necessity are nested. He gives a possible counterexample in footnote 7. |
| 14685 | Metaphysical necessity is NOT truth in all (unrestricted) worlds; necessity comes first, and is restricted [Salmon,N] |
| Full Idea: A mythology gave us the idea that metaphysical necessity is truth in every world whatsoever, without restriction. But the notion of metaphysical modality comes first, and, like every notion of modality, it is restricted. | |
| From: Nathan Salmon (The Logic of What Might Have Been [1989], IV) |
| 14690 | In the S5 account, nested modalities may be unseen, but they are still there [Salmon,N] |
| Full Idea: The S5 theorist's miscontrual of English (in the meaning of 'possibly possible') makes nested modality unseen, but it does not make nested modality vanish. Inaccessible worlds are still worlds. | |
| From: Nathan Salmon (The Logic of What Might Have Been [1989], IV) |
| 14688 | Without impossible worlds, the unrestricted modality that is metaphysical has S5 logic [Salmon,N] |
| Full Idea: If one confines one's sights to genuinely possible worlds, disavowing the impossible worlds, then metaphysical modality emerges as the limiting case - the 'unrestricted' modality that takes account of 'every' world - and S5 emerges as its proper logic. | |
| From: Nathan Salmon (The Logic of What Might Have Been [1989], IV) | |
| A reaction: He observes that this makes metaphysical modality 'restricted' simply because you have restricted what 'all worlds' means. Could there be non-maximal worlds? Are logical and metaphysical modality coextensive? I think I like the S5 view. |
| 14677 | Metaphysical necessity is said to be unrestricted necessity, true in every world whatsoever [Salmon,N] |
| Full Idea: It is held that it is the hallmark of metaphysical necessity is that it is completely unrestricted, the limiting case of restricted necessity, with no restrictions whatever. A proposition is necessary only if it is true in absolutely every world whatever. | |
| From: Nathan Salmon (The Logic of What Might Have Been [1989], II) | |
| A reaction: This is the standard picture which leads to the claim that S5 modal logic is appropriate for metaphysical necessity, because there are no restrictions on accessibility. Salmon raises objections to this conventional view. |
| 14679 | Bizarre identities are logically but not metaphysically possible, so metaphysical modality is restricted [Salmon,N] |
| Full Idea: Though there is a way things logically could be according to which I am a credit card account, there is no way things metaphysically might be according to which I am a credit card account. This illustrates the restricted nature of metaphysical modality. | |
| From: Nathan Salmon (The Logic of What Might Have Been [1989], III) | |
| A reaction: His drift is that metaphyical modality is restricted, but expressing it in S5 modal logic (where all worlds see one another) makes it unrestricted, so S5 logic is wrong for metaphysics. I'm impressed by his arguments. |
| 15230 | Logical necessity is grounded in the logical form of a statement [Harré/Madden] |
| Full Idea: When the logical form of a statement is offered as the grounds for the judgement that it cannot be true we have logical necessity. | |
| From: Harré,R./Madden,E.H. (Causal Powers [1975], 1.V.B) | |
| A reaction: This sounds like a truth about logical necessity, but certainly not a full account of it, because contingent statements also have logical form. I can't think of any other criterion than the finding of a contradiction buried in the logical form. |
| 14681 | Logical necessity is free of constraints, and may accommodate all of S5 logic [Salmon,N] |
| Full Idea: With its freedom from the constraint of metaphysical possibility, logical necessity may be construed as accommodating all the axioms and rules of S5. | |
| From: Nathan Salmon (The Logic of What Might Have Been [1989], III) | |
| A reaction: He goes on to raise problems for this simple thought. The big question: what are the limits of what is actually possible? Compare: what are the limits of what is imaginable? what are the limits of what is meaningfully sayable? |
| 15221 | The relation between what a thing is and what it can do or undergo relate by natural necessity [Harré/Madden] |
| Full Idea: The relation between what a thing is and what it is capable of doing and undergoing is naturally necessary. | |
| From: Harré,R./Madden,E.H. (Causal Powers [1975], 1.II.C) | |
| A reaction: Note that this was written in 1975, and in no way rests of Kripkean notions of rigid designation and necessary identities. Needs thought, but I take it to be an appealing proposal. |
| 15214 | Natural necessity is not logical necessity or empirical contingency in disguise [Harré/Madden] |
| Full Idea: Natural necessity is neither a mere reflection of logical necessity nor a roundabout way of referring to empirical contingency. | |
| From: Harré,R./Madden,E.H. (Causal Powers [1975], 1.I.B) | |
| A reaction: They offer a strong defence of natural necessity, which is basic to their scientific essentialism. The key point is that they, unlike some others, are not defending metaphysical necessity about nature, but finding a different type of necessity. Good. |
| 15232 | Natural necessity is when powerful particulars must produce certain results in a situation [Harré/Madden] |
| Full Idea: When the natures of the operative powerful particulars, the constraining or stimulating effect of conditions and so on are offered as the grounds for the judgement that a certain effect cannot but happen (or fail), we have natural necessity. | |
| From: Harré,R./Madden,E.H. (Causal Powers [1975], 1.V.B) | |
| A reaction: This is the view I subscribe to, the really right bit of scientific essentialism. Can this view be proved? Hm. I take the opposite view to be the misguided Humean idea that if you can imagine it not happening, then it might not happen. Firey furnace. |
| 15288 | People doubt science because if it isn't logically necessary it seems to be absolutely contingent [Harré/Madden] |
| Full Idea: At the basis of all doubts about the rationality of science lies the idea that there is no rational resting place between logical necessity and absolute contingency. | |
| From: Harré,R./Madden,E.H. (Causal Powers [1975], 7.III) | |
| A reaction: I'm struck by the fact that when someone says "I have to go now", they express a necessity. Are there thousands of types of necessity, or one conditional necessity resting on thousands of different foundations? |
| 15289 | Property or event relations are naturally necessary if generated by essential mechanisms [Harré/Madden] |
| Full Idea: The relationship between co-existing properties or successive events or states is naturally necessary when understood by scientists to be related by generative mechanisms, whose structure and components constitute the essential natures of the world. | |
| From: Harré,R./Madden,E.H. (Causal Powers [1975], 7.III) | |
| A reaction: Does that mean that the relationship between an actual state and a possible state is metaphysically necessary, rather than naturally necessary? I think we need dispositions to be part of actuality, and hence replace 'co-existing' with 'possible'. |
| 14676 | Nomological necessity is expressed with intransitive relations in modal semantics [Salmon,N] |
| Full Idea: Intransitive relations are introduced into modal semantics for the purposes of interpreting various 'real' or restricted types of modalities, such as nomological necessity. | |
| From: Nathan Salmon (The Logic of What Might Have Been [1989], II) | |
| A reaction: The point here is that the (so-called) 'laws of nature' are held to change from world to world, so necessity in one could peter out in some more remote world, rather than being carried over everywhere. A very Humean view of such things. |
| 15224 | A necessity corresponds to the nature of the actual [Harré/Madden] |
| Full Idea: There is a necessity corresponding to the nature of the actual. | |
| From: Harré,R./Madden,E.H. (Causal Powers [1975], 1.III.C) | |
| A reaction: A nice slogan for the assertion of a genuine and distinct natural necessity. Hence every possible world will have its own distinctive natural necessity. If the actual contains the possible, then there are possible new natural necessities in the actual! |
| 15231 | Transcendental necessity is conditions of a world required for a rational being to know its nature [Harré/Madden] |
| Full Idea: When the conditions for a rational being having knowledge of the nature of a world are offered as the grounds for the judgement that such a world must have certain characteristics, we have transcendental necessity. | |
| From: Harré,R./Madden,E.H. (Causal Powers [1975], 1.V.B) | |
| A reaction: It seems like a rather hard call to decide whether such characteristics pertain to the world, or to the mind of the rational being. Kant is obviously behind this one. You must read his first Critique at least four times to evaluate it. |
| 15234 | There is a transcendental necessity for each logical necessity, but the transcendental extends further [Harré/Madden] |
| Full Idea: Whatever is logically necessary must be reflected in a corresponding transcendental necessity. But there are a great range of transcendental necessities which are not reflected in any logical necessity. | |
| From: Harré,R./Madden,E.H. (Causal Powers [1975], 1.V.C) | |
| A reaction: That is, the world would be unknowable if any of the logical necessities failed to apply to it. I hope that doesn't mean that we are supposed to intuitively know all the logical necessities. Nowadays we are famous for being bad at that. |