15 ideas
| 18739 | Three stages of philosophical logic: syntactic (1905-55), possible worlds (1963-85), widening (1990-) [Horsten/Pettigrew] |
| Full Idea: Three periods can be distinguished in philosophical logic: the syntactic stage, from Russell's definite descriptions to the 1950s, the dominance of possible world semantics from the 50s to 80s, and a current widening of the subject. | |
| From: Horsten,L/Pettigrew,R (Mathematical Methods in Philosophy [2014], 1) | |
| A reaction: [compressed] I've read elsewhere that the arrival of Tarski's account of truth in 1933, taking things beyond the syntactic, was also a landmark. |
| 8132 | We now have a much more sophisticated understanding of logical form in language [Burge] |
| Full Idea: The second half of the twentieth century has seen the development of a vastly more sophisticated sense of logical form, as applied to natural languages. | |
| From: Tyler Burge (Philosophy of Mind: 1950-2000 [2005], p.462) | |
| A reaction: Burge cites this as one of the three big modern developments (along with the critique of logical positivism, and direct reference/anti-individualism). Vagueness may be the last frontier for this development. |
| 18741 | Logical formalization makes concepts precise, and also shows their interrelation [Horsten/Pettigrew] |
| Full Idea: Logical formalization forces the investigator to make the central philosophical concepts precise. It can also show how some philosophical concepts and objects can be defined in terms of others. | |
| From: Horsten,L/Pettigrew,R (Mathematical Methods in Philosophy [2014], 2) | |
| A reaction: This is the main rationale of the highly formal and mathematical approach to such things. The downside is when you impose 'precision' on language that was never intended to be precise. |
| 18744 | Models are sets with functions and relations, and truth built up from the components [Horsten/Pettigrew] |
| Full Idea: A (logical) model is a set with functions and relations defined on it that specify the denotation of the non-logical vocabulary. A series of recursive clauses explicate how truth values of complex sentences are compositionally determined from the parts. | |
| From: Horsten,L/Pettigrew,R (Mathematical Methods in Philosophy [2014], 3) | |
| A reaction: See the ideas on 'Functions in logic' and 'Relations in logic' (in the alphabetical list) to expand this important idea. |
| 6368 | If my ticket won't win the lottery (and it won't), no other tickets will either [Kyburg, by Pollock/Cruz] |
| Full Idea: The Lottery Paradox says you should rationally conclude that your ticket will not win the lottery, and then apply the same reasoning to all the other tickets, and conclude that no ticket will win the lottery. | |
| From: report of Henry E. Kyburg Jr (Probability and Logic of Rational Belief [1961]) by J Pollock / J Cruz - Contemporary theories of Knowledge (2nd) §7.2.8 | |
| A reaction: (Very compressed by me). I doubt whether this is a very deep paradox; the conclusion that I will not win is a rational assessment of likelihood, but it is not the result of strict logic. |
| 18740 | If 'exist' doesn't express a property, we can hardly ask for its essence [Horsten/Pettigrew] |
| Full Idea: If there is indeed no property of existence that is expressed by the word 'exist', then it makes no sense to ask for its essence. | |
| From: Horsten,L/Pettigrew,R (Mathematical Methods in Philosophy [2014], 2) | |
| A reaction: As far as I can tell, this was exactly Aristotle's conclusion, so he skirted round the question of 'being qua being', and focused on the nature of objects instead. Grand continental talk of 'Being' doesn't sound very interesting. |
| 18745 | A Tarskian model can be seen as a possible state of affairs [Horsten/Pettigrew] |
| Full Idea: A Tarskian model can in a sense be seen as a model of a possible state of affairs. | |
| From: Horsten,L/Pettigrew,R (Mathematical Methods in Philosophy [2014], 3) | |
| A reaction: I include this remark to show how possible worlds semantics built on the arrival of model theory. |
| 18747 | The 'spheres model' was added to possible worlds, to cope with counterfactuals [Horsten/Pettigrew] |
| Full Idea: The notion of a possible worlds model was extended (resulting in the concept of a 'spheres model') in order to obtain a satisfactory logical treatment of counterfactual conditional sentences. | |
| From: Horsten,L/Pettigrew,R (Mathematical Methods in Philosophy [2014], 4) | |
| A reaction: Thus we add 'centred' worlds, and an 'actual' world, to the loose original model. It is important to remember when we discuss 'close' worlds that we are then committed to these presuppositions. |
| 18748 | Epistemic logic introduced impossible worlds [Horsten/Pettigrew] |
| Full Idea: The idea of 'impossible worlds' was introduced into epistemic logic. | |
| From: Horsten,L/Pettigrew,R (Mathematical Methods in Philosophy [2014], 4) | |
| A reaction: Nathan Salmon seems interested in their role in metaphysics (presumably in relation to Meinongian impossible objects, like circular squares, which must necessarily be circular). |
| 18746 | Possible worlds models contain sets of possible worlds; this is a large metaphysical commitment [Horsten/Pettigrew] |
| Full Idea: Each possible worlds model contains a set of possible worlds. For this reason, possible worlds semantics is often charged with smuggling in heavy metaphysical commitments. | |
| From: Horsten,L/Pettigrew,R (Mathematical Methods in Philosophy [2014], 3) | |
| A reaction: To a beginner it looks very odd that you should try to explain possibility by constructing a model of it in terms of 'possible' worlds. |
| 18750 | Using possible worlds for knowledge and morality may be a step too far [Horsten/Pettigrew] |
| Full Idea: When the possible worlds semantics were further extended to model notions of knowledge and of moral obligation, the application was beginning to look distinctly forced and artificial. | |
| From: Horsten,L/Pettigrew,R (Mathematical Methods in Philosophy [2014], 5) | |
| A reaction: They accept lots of successes in modelling necessity and time. |
| 8126 | Anti-individualism says the environment is involved in the individuation of some mental states [Burge] |
| Full Idea: Anti-individualism is the view that not all of an individual's mental states and events can be type-individuated independently of the nature of the entities in the individual's physical or social environment environment. | |
| From: Tyler Burge (Philosophy of Mind: 1950-2000 [2005], p.453) | |
| A reaction: While the Twin Earth experiment emphasises the physical environment, Burge has been responsible for emphasising the social environment. The suspicion is that the whole concept of 'individual' minds will collapse on this view. |
| 8127 | Broad concepts suggest an extension of the mind into the environment (less computer-like) [Burge] |
| Full Idea: Certain thought experiments made trouble for standard functionalism, which limits input/output to the surface of an individual; proposals to extend this into the environment reduces the reliance on a computer paradigm, but increases complexity. | |
| From: Tyler Burge (Philosophy of Mind: 1950-2000 [2005], p.454) | |
| A reaction: [He has the Twin Earth experiment in mind] The jury is out on this, but it looks a bit of a slippery slope. Accounts of action and responsibility need a fairly sharp concept of an individual. Externalism begins to look like just a new scepticism. |
| 8129 | Anti-individualism may be incompatible with some sorts of self-knowledge [Burge] |
| Full Idea: The idea of anti-individualism raised problems about self-knowledge. The question is whether anti-individualism is compatible with some sort of authoritative or privileged warrant for certain types of self-knowledge. | |
| From: Tyler Burge (Philosophy of Mind: 1950-2000 [2005], p.457) | |
| A reaction: [See under 'Nature of Minds' for 'Anti-individualism'] The thought is that if your mind is not entirely in your head, you can no longer be an expert on it. It might go the other way: obviously we can be self-experts, so anti-individualism is wrong. |
| 8131 | Some qualities of experience, like blurred vision, have no function at all [Burge] |
| Full Idea: There appear to be qualitative aspects of experience that have no function in the life of the organism. They constitute dysfunction or noise. Blurriness in a visual experience is an example. | |
| From: Tyler Burge (Philosophy of Mind: 1950-2000 [2005], p.460) | |
| A reaction: The best account of blurred vision would seem to be adverbial - I see 'in a blurred way' (nay, blurredly). Hence maybe blurred vision is functional, but it just isn't functioning very well. |