17 ideas
| 18696 | The vagueness of truthmaker claims makes it easier to run anti-realist arguments [Button] |
| Full Idea: The sheer lack of structure demanded by truthmaker theorists means that it is easier to run model-theoretic arguments against them than against correspondence theorists. | |
| From: Tim Button (The Limits of Reason [2013], 02.3) | |
| A reaction: Truthmaking is a vague relation, where correspondence is fairly specific. Model arguments say you can keep the sentences steady, but shuffle around what they refer to. |
| 18701 | The coherence theory says truth is coherence of thoughts, and not about objects [Button] |
| Full Idea: According to the coherence theory of truth, for our thoughts to be true is not for them to be about objects, but only for them to cohere with one another. This is rather terrifying. | |
| From: Tim Button (The Limits of Reason [2013], 14.2) | |
| A reaction: Davidson espoused this view in 1983, but then gave it up. It strikes me as either a daft view of truth, or a denial of truth. The coherence theory of justification, on the other hand, is correct. |
| 18694 | Permutation Theorem: any theory with a decent model has lots of models [Button] |
| Full Idea: The Permutation Theorem says that any theory with a non-trivial model has many distinct isomorphic models with the same domain. | |
| From: Tim Button (The Limits of Reason [2013], 02.1) | |
| A reaction: This may be the most significant claim of model theory, since Putnam has erected an argument for anti-realism on it. See the ideas of Tim Button. |
| 18692 | Realists believe in independent objects, correspondence, and fallibility of all theories [Button] |
| Full Idea: External realists have three principles: Independence - the world is objects that are independent of mind, language and theory; Correspondence - truth involves some correspondence of thoughts and things; Cartesian - an ideal theory might be false. | |
| From: Tim Button (The Limits of Reason [2013], 01.1-3) | |
| A reaction: [compressed; he cites Descartes's Demon for the third] Button is setting these up as targets. I subscribe to all three, in some form or other. Of course, as a theory approaches the success implying it is 'ideal', it becomes highly likely to be accurate. |
| 18693 | Indeterminacy arguments say if a theory can be made true, it has multiple versions [Button] |
| Full Idea: Indeterminacy arguments aim to show that if there is any way to make a theory true, then there are many ways to do so. | |
| From: Tim Button (The Limits of Reason [2013], 02.1) | |
| A reaction: Button says the simplest indeterminacy argument is Putnam's Permutation Argument - that you can shuffle the objects in a formal model, without affecting truth. But do we belief that metaphysics can be settled in this sort of way? |
| 18695 | An ideal theory can't be wholly false, because its consistency implies a true model [Button] |
| Full Idea: If realists think an ideal theory could be false, then the theory is consistent, and hence complete, and hence finitely modellable, and hence it is guaranteed that there is some way to make it true. | |
| From: Tim Button (The Limits of Reason [2013], 02.2) | |
| A reaction: [compressed] This challenges the realists' supposed claim that even the most ideal of theories could possibly be false. Presumably for a theory to be 'ideal' is not all-or-nothing. Are we capable of creating a fully ideal theory? [Löwenheim-Skolem] |
| 18700 | Cartesian scepticism doubts what is true; Kantian scepticism doubts that it is sayable [Button] |
| Full Idea: Cartesian scepticism agonises over whether our beliefs are true or false, whereas Kantian scepticism agonises over how it is even possible for beliefs to be true or false. | |
| From: Tim Button (The Limits of Reason [2013], 07.2) | |
| A reaction: Kant's question is, roughly, 'how can our thoughts succeed in being about the world?' Kantian scepticism is the more drastic, and looks vulnerable to a turning of the tables, but asking how Kantian worries can even be expressed. |
| 18698 | Predictions give the 'content' of theories, which can then be 'equivalent' or 'adequate' [Button] |
| Full Idea: The empirical 'content' of a theory is all its observable predictions. Two theories with the same predictions are empirically 'equivalent'. A theory which gets it all right at this level is empirically 'adequate'. | |
| From: Tim Button (The Limits of Reason [2013], 05.1) |
| 6668 | If the present does not exist, then consciousness must be memory of the immediate past [Marshall] |
| Full Idea: Given the paradoxical nature of the 'present' moment, maybe we should understand ALL consciousness as memory, with the split second of the 'specious present' being very vivid and very brief memory, with the rest of the mind remembering in lower degrees. | |
| From: David Marshall (talk [2004]), quoted by PG - Db (ideas) | |
| A reaction: This strikes me as a highly plausible, and very illuminating remark. For the time paradox, see Ideas 1904 and 5102. Anyone researching consciousness in the brain should think about this, because it will just be a special sort of memory neurons. |
| 18697 | A sentence's truth conditions are all the situations where it would be true [Button] |
| Full Idea: A sentence's truth conditions comprise an exhaustive list of the situations in which that sentence would be true. | |
| From: Tim Button (The Limits of Reason [2013], 03.4) | |
| A reaction: So to know its meaning you must know those conditions? Compare 'my cat is licking my finger' with 'dramatic events are happening in Ethiopia'. It should take an awful long time to grasp the second sentence. |
| 24162 | Planck introduced the idea that energy can be quantized [Baggott] |
| Full Idea: By deriving his radiation law, Planck had inadvertently introduced the idea that energy itself could be 'quantized'. | |
| From: Jim Baggott (The Quantum Story: 40 moments [2011], 01) | |
| A reaction: He earlier assumed energy is continuously variable. I presume this means that the older idea of energy is now subsumed into the concept of fields, which are quantized into particles. The powers of nature are found in the fields. |
| 21731 | Fields can be 'scalar', or 'vector', or 'tensor', or 'spinor' [Baggott] |
| Full Idea: Fields can be 'scalar', with no particular direction (pointing, but not pushing or pulling); or 'vector', with a direction (like magnetism, or Newtonian gravity); or 'tensor' (needing further parameters); or 'spinor' (depending on spin orientation). | |
| From: Jim Baggott (Farewell to Reality: fairytale physics [2013], 2 'Quantum') | |
| A reaction: [compressed] So the question is, why do they differ? What is it in the nature of each field the result in a distinctive directional feature? |
| 21730 | A 'field' is a property with a magnitude, distributed across all of space and time [Baggott] |
| Full Idea: A 'field' is defined in terms of the magnitude of some physical property distributed over every point in time and space. | |
| From: Jim Baggott (Farewell to Reality: fairytale physics [2013], 2 'Quantum') | |
| A reaction: If it involves a 'property', normal usage entails that there is some entity which possesses the property. So what's the entity? Eh? Eh? You don't know! Disappointed... |
| 24163 | Free electrons have clouds of virtual particles, arising from field interaction [Baggott] |
| Full Idea: A free electron doesn't simply persist as a point particle travelling along a predetermined, classical path; it is surrounded by a swarm of virtual particles arsising from self-interactions with its own magnetic field. | |
| From: Jim Baggott (The Quantum Story: 40 moments [2011], 19) | |
| A reaction: It seems to me important for amateurs and mere philosophers to hang on to this idea of virtual particles, because they undermine any attempt to impose a macro picture on sub-atomic events. |
| 24161 | Thermodynamics sees nature as a continuous flow of energy, as radiation and as substance [Baggott] |
| Full Idea: Thermodynamics reinforced a vision of nature as one of harmonious flow. Energy, which could be neither created nor destroyed, flowed continuously between radiation and material substance, in themselves unbroken continua. | |
| From: Jim Baggott (The Quantum Story: 40 moments [2011], 01) | |
| A reaction: Interestingly, Einstein's Special Relativity e = mc2 seems to endorse this view, by equation energy and mass. I've always wanted to know what energy is, but no one seems to know. |
| 21732 | The current standard model requires 61 particles [Baggott] |
| Full Idea: The current model requires 61 particles: three generations of two leptons and two flavours of quark, in three different colours (making 24); the anti-particles of all of these (48); 12 force particles (photon, W1, Z0, 8 gluons), and a Higgs boson. | |
| From: Jim Baggott (Farewell to Reality: fairytale physics [2013], 6 n) |
| 24160 | Particle measurements don't seem to reflect their reality [Baggott] |
| Full Idea: It seems that we can no longer assume that the particle properties we measure necessarily reflect or represent the properties of the particles as they really are. | |
| From: Jim Baggott (The Quantum Story: 40 moments [2011], Pref) | |
| A reaction: [He cites a 2006 experiment] This gives an interesting response to the Copenhagen Interpretation - that observers appear to be creating the reality they observe, because they only have 'observations', with no reality to correspond to them. I like it. |