29 ideas
21566 | 'Propositional functions' are ambiguous until the variable is given a value [Russell] |
Full Idea: By a 'propositional function' I mean something which contains a variable x, and expresses a proposition as soon as a value is assigned to x. That is to say, it differs from a proposition solely by the fact that it is ambiguous. | |
From: Bertrand Russell (The Theory of Logical Types [1910], p.216) | |
A reaction: This is Frege's notion of a 'concept', as an assertion of a predicate which still lacks a subject. |
21567 | 'All judgements made by Epimenedes are true' needs the judgements to be of the same type [Russell] |
Full Idea: Such a proposition as 'all the judgements made by Epimenedes are true' will only be prima facie capable of truth if all his judgements are of the same order. | |
From: Bertrand Russell (The Theory of Logical Types [1910], p.227) | |
A reaction: This is an attempt to use his theory of types to solve the Liar. Tarski's invocation of a meta-language is clearly in the same territory. |
23457 | Type theory cannot identify features across levels (because such predicates break the rules) [Morris,M on Russell] |
Full Idea: Russell's theory of types meant that features common to different levels of the hierarchy became uncapturable (since any attempt to capture them would involve a predicate which disobeyed the hierarchy restrictions). | |
From: comment on Bertrand Russell (The Theory of Logical Types [1910]) by Michael Morris - Guidebook to Wittgenstein's Tractatus 2H | |
A reaction: I'm not clear whether this is the main reason why type theory was abandoned. Ramsey was an important critic. |
21556 | Classes are defined by propositional functions, and functions are typed, with an axiom of reducibility [Russell, by Lackey] |
Full Idea: In Russell's mature 1910 theory of types classes are defined in terms of propositional functions, and functions themselves are regimented by a ramified theory of types mitigated by the axiom of reducibility. | |
From: report of Bertrand Russell (The Theory of Logical Types [1910]) by Douglas Lackey - Intros to Russell's 'Essays in Analysis' p.133 |
21568 | A one-variable function is only 'predicative' if it is one order above its arguments [Russell] |
Full Idea: We will define a function of one variable as 'predicative' when it is of the next order above that of its arguments, i.e. of the lowest order compatible with its having an argument. | |
From: Bertrand Russell (The Theory of Logical Types [1910], p.237) | |
A reaction: 'Predicative' just means it produces a set. This is Russell's strict restriction on which functions are predicative. |
9476 | If dispositions are more fundamental than causes, then they won't conceptually reduce to them [Bird on Lewis] |
Full Idea: Maybe a disposition is a more fundamental notion than a cause, in which case Lewis has from the very start erred in seeking a causal analysis, in a traditional, conceptual sense, of disposition terms. | |
From: comment on David Lewis (Causation [1973]) by Alexander Bird - Nature's Metaphysics 2.2.8 | |
A reaction: Is this right about Lewis? I see him as reducing both dispositions and causes to a set of bald facts, which exist in possible and actual worlds. Conditionals and counterfactuals also suffer the same fate. |
8425 | For true counterfactuals, both antecedent and consequent true is closest to actuality [Lewis] |
Full Idea: A counterfactual is non-vacuously true iff it takes less of a departure from actuality to make the consequent true along with the antecedent than it does to make the antecedent true without the consequent. | |
From: David Lewis (Causation [1973], p.197) | |
A reaction: Almost every theory proposed by Lewis hangs on the meaning of the word 'close', as used here. If you visited twenty Earth-like worlds (watch Startrek?), it would be a struggle to decide their closeness to ours in rank order. |
19712 | Maybe there is plain 'animal' knowledge, and clearly justified 'reflective' knowledge [Vahid] |
Full Idea: There is a distinction between 'animal knowledge' (which requires only apt belief), and 'reflective knowledge' (requiring both apt and justified belief). | |
From: Hamid Vahid (Externalism/Internalism [2011], 5) | |
A reaction: [He cites Sosa 1991] My inclination (Idea 19711) was to think of knowledge as a continuum (possibly with a contextual component), and this distinction doesn't change my view, though it makes the point. |
19703 | Epistemic is normally marked out from moral or pragmatic justifications by its truth-goal [Vahid] |
Full Idea: It is widely believed that epistemic justification is distinct from other species of justification such as moral or pragmatic justification in that it is intended to serve the so-called 'truth-goal'. | |
From: Hamid Vahid (Externalism/Internalism [2011], 1) | |
A reaction: Kvanvig explicitly argues against this view. He broadens the aims, but it strikes me that other aims are all intertwined with truth in some way, so I find this idea quite plausible. |
19705 | 'Mentalist' internalism seems to miss the main point, if it might not involve an agent's access [Vahid] |
Full Idea: Since mentalism remains neutral on whether mental states need be accessible to an agent ...it does not seem to do justice to the intuitions that drive paradigm internalist positions. | |
From: Hamid Vahid (Externalism/Internalism [2011], 2 A) | |
A reaction: The rival view is 'access internalism', which implies that you can act on and take responsibility for your knowledge, because you are aware of its grounding. If animals know things, that might fit the mentalist picture better. |
19706 | Strong access internalism needs actual awareness; weak versions need possibility of access [Vahid] |
Full Idea: A strong form of 'access internalism' is when an agent is required to be actually aware of the conditions that constitute justification; a weaker version loosens the accessibility condition, requiring only the ability to access the justification. | |
From: Hamid Vahid (Externalism/Internalism [2011], 2 B) | |
A reaction: The super strong version implies that you probably only know one thing at a time, so it must be nonsense. The weaker version has grey areas. I remember roughly the justification, but not the details. The justification is in my diary. Etc. |
19707 | Maybe we need access to our justification, and also to know why it justifies [Vahid] |
Full Idea: Access internalism may also have a truth-conducive conception of justification, where one should not only know what one's reasons are, but also why one's beliefs are probable on one's reasons. | |
From: Hamid Vahid (Externalism/Internalism [2011], 2 B) | |
A reaction: [he cites Bonjour 1985] Sounds reasonable. It would seem odd if you had clear access to the reason, but didn't understand it, because you had just learned it by rote. |
19709 | Internalism in epistemology over-emphasises deliberation about beliefs [Vahid] |
Full Idea: The internalist approach in epistemology seems to suggest an over-inellectualized and deliberative picture of our belief-forming activities. | |
From: Hamid Vahid (Externalism/Internalism [2011], 2.2 B) | |
A reaction: This strikes me as confused. The question is not how do I arrive at my beliefs but what justifies my believing them, and what justifies the beliefs in themselves? My head is full of daft beliefs produced by TV advertising. |
19704 | Externalism may imply that identical mental states might go with different justifications [Vahid] |
Full Idea: According to the 'mentalist' version of internalism, an externalist is someone who maintains that two people can be in the same present mental states while one has a justified belief and the other does not. | |
From: Hamid Vahid (Externalism/Internalism [2011], 2 A) | |
A reaction: It seems an unlikely coincidence, that we have identical mental states, but your is (say) reliably created but mine isn't. Nevertheless this does seem to be an implication of externalism, though not a definition of it. |
19710 | With a counterfactual account of the causal theory, we get knowledge as tracking or sensitive to truth [Vahid] |
Full Idea: The causal theory of justification was soon replaced by Nozick's construal of knowledge as counterfactually sensitive to its truth value (that is, it tracks truth). A counterfactual theory of causation connects this to the causal theory. | |
From: Hamid Vahid (Externalism/Internalism [2011], 3) | |
A reaction: This is presented as an externalist theory, close to the causal theory (and prior to the reliability theory). But how could you be 'sensitive' to a changing truth if the justification was all external? Externally supported beliefs seem ossified. |
19711 | Externalism makes the acquisition of knowledge too easy? [Vahid] |
Full Idea: Internalists say that externalism is inadequate because it makes the obtaining of knowledge and justified beliefs too easy | |
From: Hamid Vahid (Externalism/Internalism [2011], 4) | |
A reaction: This looks like a key issue in epistemology. Do children and animals have lots of knowledge, which they soak up unthinkingly, or do only thinking adults really 'know' things? Why not have degrees of knowledge? |
8424 | Determinism says there can't be two identical worlds up to a time, with identical laws, which then differ [Lewis] |
Full Idea: By determinism I mean that the prevailing laws of nature are such that there do not exist any two possible worlds which are exactly alike up to that time, which differ thereafter, and in which those laws are never violated. | |
From: David Lewis (Causation [1973], p.196) | |
A reaction: This would mean that the only way an action of free will could creep in would be if it accepted being a 'violation' of the laws of nature. Fans of free will would probably prefer to call it a 'natural' phenomenon. I'm with Lewis. |
8420 | A proposition is a set of possible worlds where it is true [Lewis] |
Full Idea: I identify a proposition with the set of possible worlds where it is true. | |
From: David Lewis (Causation [1973], p.193) | |
A reaction: As it stands, I'm baffled by this. How can 'it is raining' be a set of possible worlds? I assume it expands to refer to the truth-conditions, among possibilities as well as actualities. 'It is raining' fits all worlds where it is raining. |
8405 | A theory of causation should explain why cause precedes effect, not take it for granted [Lewis, by Field,H] |
Full Idea: Lewis thinks it is a major defect in a theory of causation that it builds in the condition that the time of the cause precede that of the effect: that cause precedes effect is something we ought to explain (which his counterfactual theory claims to do). | |
From: report of David Lewis (Causation [1973]) by Hartry Field - Causation in a Physical World | |
A reaction: My immediate reaction is that the chances of explaining such a thing are probably nil, and that we might as well just accept the direction of causation as a given. Even philosophers balk at the question 'why doesn't time go backwards?' |
8427 | I reject making the direction of causation axiomatic, since that takes too much for granted [Lewis] |
Full Idea: One might stipulate that a cause must always precede its effect, but I reject this solution. It won't solve the problem of epiphenomena, it rejects a priori any backwards causation, and it trivializes defining time-direction through causation. | |
From: David Lewis (Causation [1973], p.203) | |
A reaction: [compressed] Not strong arguments, I would say. Maybe apparent causes are never epiphenomenal. Maybe backwards causation is impossible. Maybe we must use time to define causal direction, and not vice versa. |
10392 | It is just individious discrimination to pick out one cause and label it as 'the' cause [Lewis] |
Full Idea: We sometimes single out one among all the causes of some event and call it 'the' cause. ..We may select the abnormal causes, or those under human control, or those we deem good or bad, or those we want to talk about. This is invidious discrimination. | |
From: David Lewis (Causation [1973]) | |
A reaction: This is the standard view expressed by Mill - presumably the obvious empiricist line. But if we specify 'the pre-conditions' for an event, we can't just mention ANY fact prior to the effect - there is obvious relevance. So why not for 'the' cause as well? |
8419 | The modern regularity view says a cause is a member of a minimal set of sufficient conditions [Lewis] |
Full Idea: In present-day regularity analyses, a cause is defined (roughly) as any member of any minimal set of actual conditions that are jointly sufficient, given the laws, for the existence of the effect. | |
From: David Lewis (Causation [1973], p.193) | |
A reaction: This is the view Lewis is about to reject. It seem to summarise the essence of the Mackie INUS theory. This account would make the presence of oxygen a cause of almost every human event. |
8421 | Regularity analyses could make c an effect of e, or an epiphenomenon, or inefficacious, or pre-empted [Lewis] |
Full Idea: In the regularity analysis of causes, instead of c causing e, c might turn out to be an effect of e, or an epiphenomenon, or an inefficacious effect of a genuine cause, or a pre-empted cause (by some other cause) of e. | |
From: David Lewis (Causation [1973], p.194) | |
A reaction: These are Lewis's reasons for rejecting the general regularity account, in favour of his own particular counterfactual account. It is unlikely that c would be regularly pre-empted or epiphenomenal. If we build time's direction in, it won't be an effect. |
17525 | The counterfactual view says causes are necessary (rather than sufficient) for their effects [Lewis, by Bird] |
Full Idea: The Humean idea, developed by Lewis, is that rather than being sufficient for their effects, causes are (counterfactual) necessary for their effects. | |
From: report of David Lewis (Causation [1973]) by Alexander Bird - Causation and the Manifestation of Powers p.162 |
17524 | Lewis has basic causation, counterfactuals, and a general ancestral (thus handling pre-emption) [Lewis, by Bird] |
Full Idea: Lewis's basic account has a basic causal relation, counterfactual dependence, and the general causal relation is the ancestral of this basic one. ...This is motivated by counterfactual dependence failing to be general because of the pre-emption problem. | |
From: report of David Lewis (Causation [1973]) by Alexander Bird - Causation and the Manifestation of Powers p.161 | |
A reaction: It is so nice when you struggle for ages with a topic, and then some clever person summarises it clearly for you. |
8397 | Counterfactual causation implies all laws are causal, which they aren't [Tooley on Lewis] |
Full Idea: Some counterfactuals are based on non-causal laws, such as Newton's Third Law of Motion. 'If no force one way, then no force the other'. Lewis's counterfactual analysis implies that one force causes the other, which is not the case. | |
From: comment on David Lewis (Causation [1973]) by Michael Tooley - Causation and Supervenience 5.2 | |
A reaction: So what exactly does 'cause' my punt to move forwards? Basing causal laws on counterfactual claims looks to me like putting the cart before the horse. |
8423 | My counterfactual analysis applies to particular cases, not generalisations [Lewis] |
Full Idea: My (counterfactual) analysis is meant to apply to causation in particular cases; it is not an analysis of causal generalizations. Those presumably quantify over particulars, but it is hard to match natural language to the quantifiers. | |
From: David Lewis (Causation [1973], p.195) | |
A reaction: What authority could you have for asserting a counterfactual claim, if you only had one observation? Isn't the counterfactual claim the hallmark of a generalisation? For one case, 'if not-c, then not-e' is just a speculation. |
8426 | One event causes another iff there is a causal chain from first to second [Lewis] |
Full Idea: One event is the cause of another iff there exists a causal chain leading from the first to the second. | |
From: David Lewis (Causation [1973], p.200) | |
A reaction: It will be necessary to both explain and identify a 'chain'. Some chains are extremely tenuous (Alexander could stop a barrel of beer). Go back a hundred years, and the cause of any present event is everything back then. |
4795 | Lewis's account of counterfactuals is fine if we know what a law of nature is, but it won't explain the latter [Cohen,LJ on Lewis] |
Full Idea: Lewis can elucidate the logic of counterfactuals on the assumption that you are not at all puzzled about what a law of nature is. But if you are puzzled about this, it cannot contribute anything towards resolving your puzzlement. | |
From: comment on David Lewis (Causation [1973]) by L. Jonathan Cohen - The Problem of Natural Laws p.219 | |
A reaction: This seems like a penetrating remark. The counterfactual theory is wrong, partly because it is epistemological instead of ontological, and partly because it refuses to face the really difficult problem, of what is going on out there. |