49 ideas
| 6979 | Serious metaphysics cares about entailment between sentences [Jackson] |
| Full Idea: Serious metaphysics is committed to views about which sentences entail which other sentences. | |
| From: Frank Jackson (From Metaphysics to Ethics [1998], Ch.1) | |
| A reaction: This does not say that metaphysics is only about entailment, or (even worse) only about sentences. Put another way: if we wish to be wise, we must study the implications of our beliefs. Yes. |
| 6980 | Conceptual analysis studies whether one story is made true by another story [Jackson] |
| Full Idea: Conceptual analysis is the very business of addressing when and whether a story told in one vocabulary is made true by one told in some allegedly more fundamental vocabulary. | |
| From: Frank Jackson (From Metaphysics to Ethics [1998], Ch.2) | |
| A reaction: This is a view of linguistic analysis as focusing on entailments rather than on usage or truth conditions. If philosophy is the attempt to acquire a totally consistent set of beliefs (a plausible view), then Jackson is right. |
| 6983 | Intuitions about possibilities are basic to conceptual analysis [Jackson] |
| Full Idea: Intuitions about possibilities are the bread and butter of conceptual analysis. | |
| From: Frank Jackson (From Metaphysics to Ethics [1998], Ch.3) | |
| A reaction: Hence the centrality of the debate over conceivability and possibility. Which seems to reduce to the relationship between 'intuition' and 'imagination'. Imagination is a very weak guide to what is possible, and intuition is very uncertain.... |
| 14707 | Conceptual analysis is needed to establish that metaphysical reductions respect original meanings [Jackson, by Schroeter] |
| Full Idea: On the empiricist view of meaning, the relevance of conceptual analysis to metaphysics is that it establishes that a putative reduction respects the original meaning of the target expression. | |
| From: report of Frank Jackson (From Metaphysics to Ethics [1998], p.28) by Laura Schroeter - Two-Dimensional Semantics 2.2.4 |
| 7005 | Something can only have a place in a preferred account of things if it is entailed by the account [Jackson] |
| Full Idea: The one and only way of having a place in an account told in some set of preferred terms is by being entailed by that account - a view I will refer to as the entry by entailment thesis. | |
| From: Frank Jackson (From Metaphysics to Ethics [1998], Ch.1) | |
| A reaction: How do we distinguish between the original account, which seems to be just accepted, and the additions which accrue because they are entailed by it? Why does this club distinguish members from guests? |
| 6994 | Truth supervenes on being [Jackson] |
| Full Idea: Truth supervenes on being. | |
| From: Frank Jackson (From Metaphysics to Ethics [1998], Ch.5) | |
| A reaction: A nice slogan for those of us who find the word 'truth' to be meaningful. |
| 22271 | Aristotle was the first to use schematic letters in logic [Aristotle, by Potter] |
| Full Idea: It was Aristotle who initiated the use of the letter of the (Greek) alphabet 'schematically', to stand for an unspecified piece of language of some appropriate grammatical type. | |
| From: report of Aristotle (Prior Analytics [c.328 BCE]) by Michael Potter - The Rise of Analytic Philosophy 1879-1930 02 'Aris' | |
| A reaction: Did he invent it from scratch, or borrow it from the mathematicians? Euclid labels diagrams with letters. |
| 11060 | Aristotelian syllogisms are three-part, subject-predicate, existentially committed, with laws of thought [Aristotle, by Hanna] |
| Full Idea: Aristotle's logic is based on the triadic syllogism, the distinction between subject and one-place predicates, that universal claims have existential commitment, and bivalence, excluded middle and noncontradiction. | |
| From: report of Aristotle (Prior Analytics [c.328 BCE]) by Robert Hanna - Rationality and Logic 2.2 |
| 18909 | Aristotelian sentences are made up by one of four 'formative' connectors [Aristotle, by Engelbretsen] |
| Full Idea: For Aristotle there are four formatives for sentences: 'belongs to some', 'belongs to every', 'belongs to no', and 'does not belong to every'. These are 'copulae'. Aristotle would have written 'wise belongs to some man'. | |
| From: report of Aristotle (Prior Analytics [c.328 BCE]) by George Engelbretsen - Trees, Terms and Truth 3 | |
| A reaction: A rather set-theoretic reading. This invites a Quinean scepticism about whether wisdom is some entity which can 'belong' to a person. It makes trope theory sound attractive, offering a unique wisdom that is integrated into that particular person. |
| 8080 | Aristotelian identified 256 possible syllogisms, saying that 19 are valid [Aristotle, by Devlin] |
| Full Idea: Aristotle identified four 'figures' of argument, based on combinations of Subject (S) and Predicate (P) and Middle term (M). The addition of 'all' and 'some', and 'has' and 'has not' got the property, resulted in 256 possible syllogisms, 19 of them valid. | |
| From: report of Aristotle (Prior Analytics [c.328 BCE]) by Keith Devlin - Goodbye Descartes Ch.2 | |
| A reaction: [Compressed version of Devlin] What Aristotle did was astonishing, and must be one of the key ideas of western civilization, even though a lot of his assumptions have been revised or rejected. |
| 13912 | Aristotle replaced Plato's noun-verb form with unions of pairs of terms by one of four 'copulae' [Aristotle, by Engelbretsen/Sayward] |
| Full Idea: Aristotle replaced the Platonic noun-verb account of logical syntax with a 'copular' account. A sentence is a pair of terms bound together logically (not necessarily grammatically) by one of four 'logical copulae' (every, none, some, not some). | |
| From: report of Aristotle (Prior Analytics [c.328 BCE]) by Engelbretsen,G/Sayward,C - Philosophical Logic: Intro to Advanced Topics 8 | |
| A reaction: So the four copulas are are-all, are-never, are-sometimes, and are-sometime-not. Consider 'men' and 'mortal'. Alternatively, Idea 18909. |
| 8071 | Aristotle listed nineteen valid syllogisms (though a few of them were wrong) [Aristotle, by Devlin] |
| Full Idea: Aristotle listed a total of nineteen syllogisms involved in logical reasoning, though some of the ones on his list were subsequently shown to be invalid. | |
| From: report of Aristotle (Prior Analytics [c.328 BCE], Ch.1) by Keith Devlin - Goodbye Descartes | |
| A reaction: It is quite upsetting to think that the founding genius got some of it wrong, but that just shows how subtle and complex the analysis of rational thought can be. |
| 13819 | Aristotle's said some Fs are G or some Fs are not G, forgetting that there might be no Fs [Bostock on Aristotle] |
| Full Idea: Aristotle's system accepted as correct some laws which nowadays we reject, for example |= (Some Fs are G) or (some Fs are not G). He failed to take into account the possibility of there being no Fs at all. | |
| From: comment on Aristotle (Prior Analytics [c.328 BCE]) by David Bostock - Intermediate Logic 8.4 |
| 9403 | There are three different deductions for actual terms, necessary terms and possible terms [Aristotle] |
| Full Idea: Since to belong, to belong of necessity, and to be possible to belong are different, ..there will be different deductions for each; one deduction will be from necessary terms, one from terms which belong, and one from possible terms. | |
| From: Aristotle (Prior Analytics [c.328 BCE], 29b29-35) | |
| A reaction: Fitting and Mendelsohn cite this as the earliest thoughts on modal logic. but Kneale and Kneale say that Aristotle got into a muddle, and so was unable to create a workable system. |
| 15375 | If terms change their designations in different states, they are functions from states to objects [Fitting] |
| Full Idea: The common feature of every designating term is that designation may change from state to state - thus it can be formalized by a function from states to objects. | |
| From: Melvin Fitting (Intensional Logic [2007], 3) | |
| A reaction: Specifying the objects sounds OK, but specifying states sounds rather tough. |
| 15376 | Intensional logic adds a second type of quantification, over intensional objects, or individual concepts [Fitting] |
| Full Idea: To first order modal logic (with quantification over objects) we can add a second kind of quantification, over intensions. An intensional object, or individual concept, will be modelled by a function from states to objects. | |
| From: Melvin Fitting (Intensional Logic [2007], 3.3) |
| 15378 | Awareness logic adds the restriction of an awareness function to epistemic logic [Fitting] |
| Full Idea: Awareness logic enriched Hintikka's epistemic models with an awareness function, mapping each state to the set of formulas we are aware of at that state. This reflects some bound on the resources we can bring to bear. | |
| From: Melvin Fitting (Intensional Logic [2007], 3.6.1) | |
| A reaction: [He cites Fagin and Halpern 1988 for this] |
| 15379 | Justication logics make explicit the reasons for mathematical truth in proofs [Fitting] |
| Full Idea: In justification logics, the logics of knowledge are extended by making reasons explicit. A logic of proof terms was created, with a semantics. In this, mathematical truths are known for explicit reasons, and these provide a measure of complexity. | |
| From: Melvin Fitting (Intensional Logic [2007], 3.6.1) |
| 11026 | Classical logic is deliberately extensional, in order to model mathematics [Fitting] |
| Full Idea: Mathematics is typically extensional throughout (we write 3+2=2+3 despite the two terms having different meanings). ..Classical first-order logic is extensional by design since it primarily evolved to model the reasoning of mathematics. | |
| From: Melvin Fitting (Intensional Logic [2007], §1) |
| 11148 | Deduction is when we suppose one thing, and another necessarily follows [Aristotle] |
| Full Idea: A deduction is a discourse in which, certain things having been supposed, something different from the things supposed results of necessity because these things are so. | |
| From: Aristotle (Prior Analytics [c.328 BCE], 24b18) | |
| A reaction: Notice that it is modal ('suppose', rather than 'know'), that necessity is involved, which is presumably metaphysical necessity, and that there are assumptions about what would be true, and not just what follows from what. |
| 18896 | Aristotle places terms at opposite ends, joined by a quantified copula [Aristotle, by Sommers] |
| Full Idea: Aristotle often preferred to formulate predications by placing the terms at opposite ends of the sentence and joining them by predicating expressions like 'belongs-to-some' or 'belongs-to-every'. | |
| From: report of Aristotle (Prior Analytics [c.328 BCE]) by Fred Sommers - Intellectual Autobiography 'Conceptions' | |
| A reaction: This is Sommers's picture of Aristotle, which led Sommers to develop his modern Term Logic. |
| 3300 | Aristotle's logic is based on the subject/predicate distinction, which leads him to substances and properties [Aristotle, by Benardete,JA] |
| Full Idea: Basic to Aristotle's logic is the grammatical distinction between subject and predicate, which he glosses in terms of the contrast between a substance and its properties. | |
| From: report of Aristotle (Prior Analytics [c.328 BCE]) by José A. Benardete - Metaphysics: the logical approach Intro | |
| A reaction: The introduction of quantifiers and 'logical form' can't disguise the fact that we still talk about (and with) objects and predicates, because no one can think of any other way to talk. |
| 11028 | λ-abstraction disambiguates the scope of modal operators [Fitting] |
| Full Idea: λ-abstraction can be used to abstract and disambiguate a predicate. De re is [λx◊P(x)](f) - f has the possible-P property - and de dicto is ◊[λxP(x)](f) - possibly f has the P-property. Also applies to □. | |
| From: Melvin Fitting (Intensional Logic [2007], §3.3) | |
| A reaction: Compare the Barcan formula. Originated with Church in the 1930s, and Carnap 1947, but revived by Stalnaker and Thomason 1968. Because it refers to the predicate, it has a role in intensional versions of logic, especially modal logic. |
| 11149 | Affirming/denying sentences are universal, particular, or indeterminate [Aristotle] |
| Full Idea: Affirming/denying sentences are universal, particular, or indeterminate. Belonging 'to every/to none' is universal; belonging 'to some/not to some/not to every' is particular; belonging or not belonging (without universal/particular) is indeterminate. | |
| From: Aristotle (Prior Analytics [c.328 BCE], 24a16) |
| 8079 | Aristotelian logic has two quantifiers of the subject ('all' and 'some') [Aristotle, by Devlin] |
| Full Idea: Aristotelian logic has two quantifiers of the subject ('all' and 'some'), and two ways to combine the subject with the predicate ('have', and 'have not'), giving four propositions: all-s-have-p, all-s-have-not-p, some-s-have-p, and some-s-have-not-p. | |
| From: report of Aristotle (Prior Analytics [c.328 BCE]) by Keith Devlin - Goodbye Descartes Ch.2 | |
| A reaction: Frege seems to have switched from 'some' to 'at-least-one'. Since then other quantifiers have been proposed. See, for example, Ideas 7806 and 6068. |
| 6984 | Smooth reductions preserve high-level laws in the lower level [Jackson] |
| Full Idea: In a 'smooth' reduction the laws of the reduced theory (thermodynamics of gases) are pretty much preserved in (and isomorphic with) the corresponding laws in the reducing theory (molecular or kinetic theory of gases). | |
| From: Frank Jackson (From Metaphysics to Ethics [1998], Ch.3) | |
| A reaction: Are the 'laws' of weather (e.g. linking humidity, temperature and pressure to rainfall) preserved at the level of physics? One might say that they are not preserved, but they are not lost either (they just fade away). Contradictions would be worrying. |
| 6978 | Baldness is just hair distribution, but the former is indeterminate, unlike the latter [Jackson] |
| Full Idea: Baldness is a much more indeterminate matter than is hair distribution, nevetheless baldness is nothing over and above hair distribution. | |
| From: Frank Jackson (From Metaphysics to Ethics [1998], p.22) | |
| A reaction: This seems to support Williamson's view that there is no vagueness in nature, and that 'vague' is an entirely epistemological concept. |
| 6993 | Redness is a property, but only as a presentation to normal humans [Jackson] |
| Full Idea: We typically count things as red just if they have a property that interacts with normal human beings to make the object look red in such a way that their so looking counts as a presentation of the property to normal humans. | |
| From: Frank Jackson (From Metaphysics to Ethics [1998], Ch.4) | |
| A reaction: This is Jackson's careful statement of the 'Australian' primary property view of colours. He is trying to make red a real property of objects, but personally I take the mention of 'normal' humans as a huge danger sign. Nice try, but no. See Idea 5456. |
| 6987 | We should not multiply senses of necessity beyond necessity [Jackson] |
| Full Idea: We should not multiply senses of necessity beyond necessity. | |
| From: Frank Jackson (From Metaphysics to Ethics [1998], Ch.3) | |
| A reaction: It would be nice if there was just one sense of necessity, with the multiplication arising from the different ways in which necessities arise. In chess, checkmate is a necessity which rests on contingencies. Absolute necessities seem different. |
| 14641 | A deduction is necessary if the major (but not the minor) premise is also necessary [Aristotle] |
| Full Idea: It sometimes results that the deduction becomes necessary when only one of the premises is necessary (not whatever premise it might be, however, but only the premise in relation to the major extreme [premise]). | |
| From: Aristotle (Prior Analytics [c.328 BCE], 30a15) | |
| A reaction: The qualification is brackets is said by Plantinga (1969) to be a recognition of the de re/ de dicto distinction (later taken up by Aquinas). Plantinga gives two examples to illustrate his reading. |
| 6988 | Mathematical sentences are a problem in a possible-worlds framework [Jackson] |
| Full Idea: There is notoriously a problem about what to say concerning mathematical sentences within the possible-worlds framework. | |
| From: Frank Jackson (From Metaphysics to Ethics [1998], Ch.3 n25) | |
| A reaction: Presumably this concerns possible axioms and their combinations. |
| 6975 | Possible worlds could be concrete, abstract, universals, sentences, or properties [Jackson] |
| Full Idea: Possible worlds might be concrete (Lewis), or abstract (Stalnaker), or structured universals (Forrest), or collections of sentences (Jeffrey), or mere combinations of properties and relations (Armstrong). | |
| From: Frank Jackson (From Metaphysics to Ethics [1998], Ch.1) | |
| A reaction: A helpful summary. I don't like concrete, or collections of sentences. Whatever they are, they had better be 'possible', so not any old collection or idea will do. |
| 15377 | Definite descriptions pick out different objects in different possible worlds [Fitting] |
| Full Idea: Definite descriptions pick out different objects in different possible worlds quite naturally. | |
| From: Melvin Fitting (Intensional Logic [2007], 3.4) | |
| A reaction: A definite description can pick out the same object in another possible world, or a very similar one, or an object which has almost nothing in common with the others. |
| 6982 | Long arithmetic calculations show the a priori can be fallible [Jackson] |
| Full Idea: We know that being fallible and being a priori can co-exist - the results of long numerical additions are well-known examples. | |
| From: Frank Jackson (From Metaphysics to Ethics [1998], Ch.2) | |
| A reaction: I see this realisation as a good example of progress in philosophy. Russell, who says self-evidence comes in degrees, deserves major credit. It is the key idea that once again makes rationalism respectable. |
| 6991 | We examine objects to determine colour; we do not introspect [Jackson] |
| Full Idea: We examine objects to determine their colour; we do not introspect. | |
| From: Frank Jackson (From Metaphysics to Ethics [1998], Ch.3) | |
| A reaction: Interesting, but the theory of secondary qualities did not arise from experience, but from a theory about what is actually going on. Compare pain appearing to be in your foot. |
| 18911 | Linguistic terms form a hierarchy, with higher terms predicable of increasing numbers of things [Aristotle, by Engelbretsen] |
| Full Idea: According to Aristotle, the terms of a language form a finite hierarchy, where the higher terms are predicable of more things than are lower terms. | |
| From: report of Aristotle (Prior Analytics [c.328 BCE]) by George Engelbretsen - Trees, Terms and Truth 3 | |
| A reaction: I would be a bit cautious about placing something precisely in a hierarchy according to how many things it can be predicated of. It is a start, though, in trying to give a decent account of generality, which is a major concept in philosophy. |
| 6976 | In physicalism, the psychological depends on the physical, not the other way around [Jackson] |
| Full Idea: Physicalism is associated with various asymmetry doctrines, most famously with the idea that the psychological depends in some sense on the physical, and not the other way around. | |
| From: Frank Jackson (From Metaphysics to Ethics [1998], Ch.1) | |
| A reaction: Sounds okay to me. Shadows depend on objects, and not the other way round. It might suggest properties depending on substances (or bare particulars), but I prefer the dependence of processes on mechanisms (waterfalls on liquid water). |
| 6986 | Is the dependence of the psychological on the physical a priori or a posteriori? [Jackson] |
| Full Idea: Should the necessary passage from the physical account of the world to the psychological one that physicalists are committed to, be placed in the a posteriori or the a priori basket? | |
| From: Frank Jackson (From Metaphysics to Ethics [1998], Ch.3) | |
| A reaction: That is, is 'the physical entails the mental' empirical or a priori? See Idea 3989. If we can at least dream of substance dualism, it is hard to see how it could be fully a priori. I think I prefer to see it as an inductive explanation. |
| 6992 | If different states can fulfil the same role, the converse must also be possible [Jackson] |
| Full Idea: It would be strange if having learnt the lesson of multiple realisability that the same role may be filled by different states, we turned around and insisted that the converse - different roles filled by the same state - is impossible. | |
| From: Frank Jackson (From Metaphysics to Ethics [1998], Ch.4 n3) | |
| A reaction: Good. The world is full of creatures who seem to enjoy the smell of decay etc. Some people (not me) like horror films. The separation of qualia and role leaves type-type physicalism as a possibility. Survival needs similar roles, not similar qualia. |
| 6996 | Folk psychology covers input, internal role, and output [Jackson] |
| Full Idea: Folk psychology has a tripartite nature, with input clauses, internal role clauses, and output clauses. | |
| From: Frank Jackson (From Metaphysics to Ethics [1998], Ch.5) | |
| A reaction: Interesting, particularly that folk psychology refers to internal roles, or attempts to explain what is going on inside the 'black box'. The folk have collectively worked out a standard flow diagram for human thought. |
| 6977 | Egocentric or de se content seems to be irreducibly so [Jackson] |
| Full Idea: I have been convinced by arguments (e.g. of Perry, Castañeda and Lewis) that egocentric or de se content is irreducibly so. | |
| From: Frank Jackson (From Metaphysics to Ethics [1998], Ch.1) | |
| A reaction: This is associated with the use of indexicals (like 'I' and 'now') in language. Quine disagrees, and should not be written off. Any theory of content, concepts, meaning etc. must clearly taken account of such subjective language. |
| 6990 | Keep distinct the essential properties of water, and application conditions for the word 'water' [Jackson] |
| Full Idea: My guess is that objectors to the deflationary account of the Twin Earth parable are confusing the essential properties of water with the question of what is essential for being water. | |
| From: Frank Jackson (From Metaphysics to Ethics [1998], Ch.3) | |
| A reaction: That is, we must distinguish between the actual ontology of water's properties and the conditions under which we (in our society) apply the word 'water'. Interesting. The latter issue, though, might push us back towards internalism... |
| 6985 | Analysis is finding necessary and sufficient conditions by studying possible cases [Jackson] |
| Full Idea: Conceptual analysis is sometimes understood as the business of finding necessary and sufficient conditions by the method of possible cases. | |
| From: Frank Jackson (From Metaphysics to Ethics [1998], Ch.3) | |
| A reaction: Some (e.g. Stich) reject this, but it seems to me undeniable that the procedure can be very illuminating, even if it is never totally successful. Jackson prefers to see analysis as the study of entailments between stories about the world. |
| 6995 | Successful predication supervenes on nature [Jackson] |
| Full Idea: Successful predication supervenes on nature. | |
| From: Frank Jackson (From Metaphysics to Ethics [1998], Ch.5) | |
| A reaction: A nice slogan, but it is in danger of being a tautology. If I say x and y 'are my favourites/are interesting', is that 'successful' predication? Is 'Juliet is the sun' unsuccessful? |
| 6989 | I can understand "He has a beard", without identifying 'he', and hence the truth conditions [Jackson] |
| Full Idea: If I hear someone say "He has a beard", and I don't know whether it is Jackson, Jones, or someone else, I don't know which proposition is being expressed in the sense of not knowing the conditions under which what is said is true. | |
| From: Frank Jackson (From Metaphysics to Ethics [1998], Ch.3) | |
| A reaction: This is the neatest and simplest problem I have encountered for Davidson's truth-conditions account of meaning. However, we probably just say that we understand the sense but not the reference. The strict-and-literal but not contextual meaning. |
| 6998 | Folk morality does not clearly distinguish between doing and allowing [Jackson] |
| Full Idea: We have, it seems to me, currently no clear sense of the place and rationale of the distinction between doing and allowing in folk morality. | |
| From: Frank Jackson (From Metaphysics to Ethics [1998], Ch.5) | |
| A reaction: Does this mean that philosophers should endeavour to appear on television in order to improve folk morality, so that Jackson, back at the ranch, can then infer the meanings of moral terms from the new improved version? |
| 6997 | Moral functionalism says moral terms get their meaning from their role in folk morality [Jackson] |
| Full Idea: Moral functionalism is the view that the meanings of moral terms are given by their place in the network of input, internal clauses, and output that makes up folk psychology. | |
| From: Frank Jackson (From Metaphysics to Ethics [1998], Ch.5) | |
| A reaction: Jackson considers this enough to support a cognitivist view of morality. In assuming that there is something stable called 'folk morality' he seems to be ignoring questions about cultural relativism. |
| 7000 | Which are prior - thin concepts like right, good, ought; or thick concepts like kindness, equity etc.? [Jackson] |
| Full Idea: 'Centralists' (e.g. Bernard Williams) say thin ethical concepts (right, good, ought) are conceptually fundamental; 'non-centralists' (e.g. Susan Hurley) say that such concepts are not conceptually prior to kindness, equity and the like. | |
| From: Frank Jackson (From Metaphysics to Ethics [1998], Ch.5) | |
| A reaction: My immediate intuition is to side with Susan Hurley, since morality grows out of immediate relationships, not out of intellectual principles and theoretical generalisations. This would go with particularist views of virtue theory. |
| 6999 | It is hard to justify the huge difference in our judgements of abortion and infanticide [Jackson] |
| Full Idea: We allow that abortion is permissible in many circumstances, but infanticide is hardly ever permissible, and yet it is hard to justify this disparity in moral judgement in the sense of finding the relevant difference. | |
| From: Frank Jackson (From Metaphysics to Ethics [1998], Ch.5) | |
| A reaction: The implications of this are tough to face. A foetus is (maybe) just not as important as a new-born babe - and so a new-born babe is of less importance than a five-year old. Birth is (or was) a hugely dangerous hurdle to be cleared. |