19 ideas
| 20435 | If philosophy could be summarised it would be pointless [Adorno] |
| Full Idea: Philosophy is in essence not summarisable. Otherwise it would be superfluous; that most of it allows its to be summarised speaks against it. | |
| From: Theodor W. Adorno (Negative Dialectics [1966], p.34), quoted by Gerhard Richter - Benjamin and Adorno 3 | |
| A reaction: This seems contradict the Cicero quotation which I take to be the epigraph of my collection of ideas. Adorno has a very 'continental' view, placing philosophy much closer to poetry (Heidegger's later view) than to science. Not like advocacy either. |
| 2516 | Most of philosophy begins where science leaves off [Katz] |
| Full Idea: Philosophy, or at least one large part of it, is subsequent to science; it begins where science leaves off. | |
| From: Jerrold J. Katz (Realistic Rationalism [2000], Int.xxi) | |
| A reaction: In some sense this has to be true. Without metaphysics there couldn't be any science. Rationalists should not forget, though, the huge impact which Darwin's science has (or should have) on fairly abstract philosophy (e.g. epistemology). |
| 2510 | Traditionally philosophy is an a priori enquiry into general truths about reality [Katz] |
| Full Idea: The traditional conception of philosophy is that it is an a priori enquiry into the most general facts about reality. | |
| From: Jerrold J. Katz (Realistic Rationalism [2000], Int.xi) | |
| A reaction: I think this still defines philosophy, though it also highlights the weakness of the subject, which is over-confidence about asserting necessary truths. How could the most god-like areas of human thought be about anything else? |
| 13913 | The four 'perfect syllogisms' are called Barbara, Celarent, Darii and Ferio [Engelbretsen/Sayward] |
| Full Idea: There are four 'perfect syllogisms': Barbara (every M is P, every S is M, so every S is P); Celarent (no M is P, every S is M, so no S is P); Darii (every M is P, some S is M, so some S is P); Ferio (no M is P, some S is M, so some S is not P). | |
| From: Engelbretsen,G/Sayward,C (Philosophical Logic: Intro to Advanced Topics [2011], 8) | |
| A reaction: The four names are mnemonics from medieval universities. |
| 13914 | Syllogistic logic has one rule: what is affirmed/denied of wholes is affirmed/denied of their parts [Engelbretsen/Sayward] |
| Full Idea: It has often been claimed (e.g. by Leibniz) that a single rule governs all syllogistic validity, called 'dictum de omni et null', which says that what is affirmed or denied of any whole is affirmed or denied of any part of that whole. | |
| From: Engelbretsen,G/Sayward,C (Philosophical Logic: Intro to Advanced Topics [2011], 8) | |
| A reaction: This seems to be the rule which is captured by Venn Diagrams. |
| 13915 | Syllogistic can't handle sentences with singular terms, or relational terms, or compound sentences [Engelbretsen/Sayward] |
| Full Idea: Three common kinds of sentence cannot be put into syllogistic ('categorical') form: ones using singular terms ('Mars is red'), ones using relational terms ('every painter owns some brushes'), and compound sentences. | |
| From: Engelbretsen,G/Sayward,C (Philosophical Logic: Intro to Advanced Topics [2011], 8) |
| 13916 | Term logic uses expression letters and brackets, and '-' for negative terms, and '+' for compound terms [Engelbretsen/Sayward] |
| Full Idea: Term logic begins with expressions and two 'term functors'. Any simple letter is a 'term', any term prefixed by a minus ('-') is a 'negative term', and any pair of terms flanking a plus ('+') is a 'compound term'. Parenthese are used for grouping. | |
| From: Engelbretsen,G/Sayward,C (Philosophical Logic: Intro to Advanced Topics [2011], 8) | |
| A reaction: [see Engelbretsen and Sayward for the full formal system] |
| 13850 | In modern logic all formal validity can be characterised syntactically [Engelbretsen/Sayward] |
| Full Idea: One of the key ideas of modern formal logic is that all formally valid inferences can be specified in strictly syntactic terms. | |
| From: Engelbretsen,G/Sayward,C (Philosophical Logic: Intro to Advanced Topics [2011], Ch.2) |
| 13849 | Classical logic rests on truth and models, where constructivist logic rests on defence and refutation [Engelbretsen/Sayward] |
| Full Idea: Classical logic rests on the concepts of truth and falsity (and usually makes use of a semantic theory based on models), whereas constructivist logic accounts for inference in terms of defense and refutation. | |
| From: Engelbretsen,G/Sayward,C (Philosophical Logic: Intro to Advanced Topics [2011], Intro) | |
| A reaction: My instincts go with the classical view, which is that inferences do not depend on the human capacity to defend them, but sit there awaiting revelation. My view isn't platonist, because I take the inferences to be rooted in the physical world. |
| 13851 | Unlike most other signs, = cannot be eliminated [Engelbretsen/Sayward] |
| Full Idea: Unlike ∨, →, ↔, and ∀, the sign = is not eliminable from a logic. | |
| From: Engelbretsen,G/Sayward,C (Philosophical Logic: Intro to Advanced Topics [2011], Ch.3) |
| 13852 | Axioms are ω-incomplete if the instances are all derivable, but the universal quantification isn't [Engelbretsen/Sayward] |
| Full Idea: A set of axioms is said to be ω-incomplete if, for some universal quantification, each of its instances is derivable from those axioms but the quantification is not thus derivable. | |
| From: Engelbretsen,G/Sayward,C (Philosophical Logic: Intro to Advanced Topics [2011], 7) |
| 2521 | 'Real' maths objects have no causal role, no determinate reference, and no abstract/concrete distinction [Katz] |
| Full Idea: Three objections to realism in philosophy of mathematics: mathematical objects have no space/time location, and so no causal role; that such objects are determinate, but reference to numbers aren't; and that there is no abstract/concrete distinction. | |
| From: Jerrold J. Katz (Realistic Rationalism [2000], Int.xxix) |
| 2513 | We don't have a clear enough sense of meaning to pronounce some sentences meaningless or just analytic [Katz] |
| Full Idea: Linguistic meaning is not rich enough to show either that all metaphysical sentences are meaningless or that all alleged synthetic a priori propositions are just analytic a priori propositions. | |
| From: Jerrold J. Katz (Realistic Rationalism [2000], Int.xx) |
| 2522 | Experience cannot teach us why maths and logic are necessary [Katz] |
| Full Idea: The Leibniz-Kant criticism of empiricism is that experience cannot teach us why mathematical and logical facts couldn't be otherwise than they are. | |
| From: Jerrold J. Katz (Realistic Rationalism [2000], Int.xxxi) |
| 2517 | Structuralists see meaning behaviouristically, and Chomsky says nothing about it [Katz] |
| Full Idea: In linguistics there are two schools of thought: Bloomfieldian structuralism (favoured by Quine) conceives of sentences acoustically and meanings behaviouristically; and Chomskian generative grammar (which is silent about semantics). | |
| From: Jerrold J. Katz (Realistic Rationalism [2000], Int.xxiv) | |
| A reaction: They both appear to be wrong, so there is (or was) something rotten in the state of linguistics. Are the only options for meaning either behaviourist or eliminativist? |
| 2519 | It is generally accepted that sense is defined as the determiner of reference [Katz] |
| Full Idea: There is virtually universal acceptance of Frege's definition of sense as the determiner of reference. | |
| From: Jerrold J. Katz (Realistic Rationalism [2000], Int.xxvi) | |
| A reaction: Not any more, since Kripke and Putnam. It is one thing to say sense determines reference, and quite another to say that this is the definition of sense. |
| 2520 | Sense determines meaning and synonymy, not referential properties like denotation and truth [Katz] |
| Full Idea: Pace Frege, sense determines sense properties and relations, like meaningfulness and synonymy, rather than determining referential properties, like denotation and truth. | |
| From: Jerrold J. Katz (Realistic Rationalism [2000], Int.xxvi) | |
| A reaction: This leaves room for Fregean 'sense', after Kripke has demolished the idea that sense determines reference. |
| 2518 | Sentences are abstract types (like musical scores), not individual tokens [Katz] |
| Full Idea: Sentences are types, not utterance tokens or mental/neural tokens, and hence sentences are abstract objects (like musical scores). | |
| From: Jerrold J. Katz (Realistic Rationalism [2000], Int.xxvi) | |
| A reaction: If sentences are abstract types, then two verbally indistinguishable sentences are the same sentence. But if I say 'I am happy', that isn't the same as you saying it. |
| 15664 | Ideology is 'socially necessary illusion' or 'socially necessary false-consciousness' [Adorno, by Finlayson] |
| Full Idea: Adorno defines ideology as 'socially necessary illusion' or 'socially necessary false-consciousness' (and the young Habermas accepted something like this definition). | |
| From: report of Theodor W. Adorno (works [1955]) by James Gordon Finlayson - Habermas Ch.1:11 | |
| A reaction: The marxism seems to reside in the view that such things are always 'false'. If they gradually became 'true', would they cease to be ideology? Is it impossible for widespread beliefs to be 'true'? |