16 ideas
| 13966 | Analytic philosophy loved the necessary a priori analytic, linguistic modality, and rigour [Soames] |
| Full Idea: The golden age of analytic philosophy (mid 20th c) was when necessary, a priori and analytic were one, all possibility was linguistic possibility, and the linguistic turn gave philosophy a respectable subject matter (language), and precision and rigour. | |
| From: Scott Soames (Significance of the Kripkean Nec A Posteriori [2006], p.166) | |
| A reaction: Gently sarcastic, because Soames is part of the team who have put a bomb under this view, and quite right too. Personally I think the biggest enemy in all of this lot is not 'language' but 'rigour'. A will-o-the-wisp philosophers dream of. |
| 13974 | If philosophy is analysis of meaning, available to all competent speakers, what's left for philosophers? [Soames] |
| Full Idea: If all of philosophy is the analysis of meaning, and meaning is fundamentally transparent to competent speakers, there is little room for philosophically significant explanations and theories, since they will be necessary or a priori, or both. | |
| From: Scott Soames (Significance of the Kripkean Nec A Posteriori [2006], p.186) | |
| A reaction: He cites the later Wittgenstein as having fallen into this trap. I suppose any area of life can have its specialists, but I take Shakespeare to be a greater master of English than any philosopher I have ever read. |
| 10282 | Logic is the study of sound argument, or of certain artificial languages (or applying the latter to the former) [Hodges,W] |
| Full Idea: A logic is a collection of closely related artificial languages, and its older meaning is the study of the rules of sound argument. The languages can be used as a framework for studying rules of argument. | |
| From: Wilfrid Hodges (First-Order Logic [2001], 1.1) | |
| A reaction: [Hodges then says he will stick to the languages] The suspicion is that one might confine the subject to the artificial languages simply because it is easier, and avoids the tricky philosophical questions. That approximates to computer programming. |
| 10283 | A formula needs an 'interpretation' of its constants, and a 'valuation' of its variables [Hodges,W] |
| Full Idea: To have a truth-value, a first-order formula needs an 'interpretation' (I) of its constants, and a 'valuation' (ν) of its variables. Something in the world is attached to the constants; objects are attached to variables. | |
| From: Wilfrid Hodges (First-Order Logic [2001], 1.3) |
| 10284 | There are three different standard presentations of semantics [Hodges,W] |
| Full Idea: Semantic rules can be presented in 'Tarski style', where the interpretation-plus-valuation is reduced to the same question for simpler formulas, or the 'Henkin-Hintikka style' in terms of games, or the 'Barwise-Etchemendy style' for computers. | |
| From: Wilfrid Hodges (First-Order Logic [2001], 1.3) | |
| A reaction: I haven't yet got the hang of the latter two, but I note them to map the territory. |
| 10285 | I |= φ means that the formula φ is true in the interpretation I [Hodges,W] |
| Full Idea: I |= φ means that the formula φ is true in the interpretation I. | |
| From: Wilfrid Hodges (First-Order Logic [2001], 1.5) | |
| A reaction: [There should be no space between the vertical and the two horizontals!] This contrasts with |-, which means 'is proved in'. That is a syntactic or proof-theoretic symbol, whereas |= is a semantic symbol (involving truth). |
| 10288 | Down Löwenheim-Skolem: if a countable language has a consistent theory, that has a countable model [Hodges,W] |
| Full Idea: Downward Löwenheim-Skolem (the weakest form): If L is a first-order language with at most countably many formulas, and T is a consistent theory in L. Then T has a model with at most countably many elements. | |
| From: Wilfrid Hodges (First-Order Logic [2001], 1.10) |
| 10289 | Up Löwenheim-Skolem: if infinite models, then arbitrarily large models [Hodges,W] |
| Full Idea: Upward Löwenheim-Skolem: every first-order theory with infinite models has arbitrarily large models. | |
| From: Wilfrid Hodges (First-Order Logic [2001], 1.10) |
| 10287 | If a first-order theory entails a sentence, there is a finite subset of the theory which entails it [Hodges,W] |
| Full Idea: Compactness Theorem: suppose T is a first-order theory, ψ is a first-order sentence, and T entails ψ. Then there is a finite subset U of T such that U entails ψ. | |
| From: Wilfrid Hodges (First-Order Logic [2001], 1.10) | |
| A reaction: If entailment is possible, it can be done finitely. |
| 10286 | A 'set' is a mathematically well-behaved class [Hodges,W] |
| Full Idea: A 'set' is a mathematically well-behaved class. | |
| From: Wilfrid Hodges (First-Order Logic [2001], 1.6) |
| 13969 | Kripkean essential properties and relations are necessary, in all genuinely possible worlds [Soames] |
| Full Idea: By (Kripkean) 'essential' properties and relations I mean simply properties and relations that hold necessarily of objects (in all genuinely possible world-states in which the objects exist). | |
| From: Scott Soames (Significance of the Kripkean Nec A Posteriori [2006], p.168 n5) | |
| A reaction: This is the standard modern view of essences which I find so unsatisfactory. Kit Fine has helped to take us back to the proper Aristotelian view, where 'necessary' and 'essential' actually have different meanings. Note the inclusion of relations. |
| 13973 | A key achievement of Kripke is showing that important modalities are not linguistic in source [Soames] |
| Full Idea: None of Kripke's many achievements is more important than his breaking the spell of the linguistic as the source of philosophically important modalities. | |
| From: Scott Soames (Significance of the Kripkean Nec A Posteriori [2006], p.186) | |
| A reaction: Put like that, Kripke may have had the single most important thought of modern times. I take good philosophy to be exactly the same as good scientific theorising, in that it all arises out of the nature of reality (and I include logic in that). |
| 13968 | Kripkean possible worlds are abstract maximal states in which the real world could have been [Soames] |
| Full Idea: For the Kripkean possible states of the world are not alternate concrete universes, but abstract objects. Metaphysically possible world-states are maximally complete ways the real concrete universe could have been. | |
| From: Scott Soames (Significance of the Kripkean Nec A Posteriori [2006], p.167) | |
| A reaction: This is probably clearer about the Kripkean view than Kripke ever is, but then that is part of Soames's mission. It sounds like the right way to conceive possible worlds. At least there is some commitment there, rather than instrumentalism about them. |
| 13972 | Two-dimensionalism reinstates descriptivism, and reconnects necessity and apriority to analyticity [Soames] |
| Full Idea: Two-dimensionalism is a fundamentally anti-Kripkean attempt to reinstate descriptivism about names and natural kind terms, to reconnect necessity and apriority to analyticity, and return philosophy to analytic paradigms of its golden age. | |
| From: Scott Soames (Significance of the Kripkean Nec A Posteriori [2006], p.183) | |
| A reaction: I presume this is right, and it is so frustrating that you need Soames to spell it out, when Chalmers is much more low-key. Philosophers hate telling you what their real game is. Why is that? |
| 1748 | Archelaus was the first person to say that the universe is boundless [Archelaus, by Diog. Laertius] |
| Full Idea: Archelaus was the first person to say that the universe is boundless. | |
| From: report of Archelaus (fragments/reports [c.450 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 02.Ar.3 |
| 5989 | Archelaus said life began in a primeval slime [Archelaus, by Schofield] |
| Full Idea: Archelaus wrote that life on Earth began in a primeval slime. | |
| From: report of Archelaus (fragments/reports [c.450 BCE]) by Malcolm Schofield - Archelaus | |
| A reaction: This sounds like a fairly clearcut assertion of the production of life by evolution. Darwin's contribution was to propose the mechanism for achieving it. We should honour the name of Archelaus for this idea. |