33 ideas
14611 | Metaphysics should avoid talk of past, present or future [Smart] |
Full Idea: Metaphysics should not be cosmically parochial. It should eschew tensed languages. | |
From: J.J.C. Smart (The Tenseless Theory of Time [2008], 1) | |
A reaction: This is quite an engaging reason to be an eternalist (or B-theorist) about time. Presumably we can still believe in tensed time, as long as we recognise that metaphysics itself is a timeless subject. |
17070 | Coherence is consilience, simplicity, analogy, and fitting into a web of belief [Smart] |
Full Idea: I shall make use of the admittedly imprecise notions of consilience, simplicity, analogy and fitting into a web of belief, or in short of 'coherence'. | |
From: J.J.C. Smart (Explanation - Opening Address [1990], p.06) | |
A reaction: Coherence sounds like a family of tests, rather than a single unified concept. I still like coherence, though. |
17072 | We need comprehensiveness, as well as self-coherence [Smart] |
Full Idea: Not mere self-coherence, but comprehensiveness belongs to the notion of coherence. | |
From: J.J.C. Smart (Explanation - Opening Address [1990], p.07) |
7807 | The laws of thought are true, but they are not the axioms of logic [Bolzano, by George/Van Evra] |
Full Idea: Bolzano said the 'laws of thought' (identity, contradiction, excluded middle) are true, but nothing of interest follows from them. Logic obeys them, but they are not logic's first principles or axioms. | |
From: report of Bernard Bolzano (Theory of Science (Wissenschaftslehre, 4 vols) [1837], §3) by George / Van Evra - The Rise of Modern Logic | |
A reaction: An interesting and crucial distinction. For samples of proposed axioms of logic, see Ideas 6408, 7798 and 7797. |
9987 | An aggregate in which order does not matter I call a 'set' [Bolzano] |
Full Idea: An aggregate whose basic conception renders the arrangement of its members a matter of indifference, and whose permutation therefore produces no essential difference, I call a 'set'. | |
From: Bernard Bolzano (Paradoxes of the Infinite [1846], §4), quoted by William W. Tait - Frege versus Cantor and Dedekind IX | |
A reaction: The idea of 'sets' was emerging before Cantor formalised it, and clarified it by thinking about infinite sets. Nowadays we also have 'ordered' sets, which rather contradicts Bolzano, and we also expect the cardinality to be determinate. |
9618 | Bolzano wanted to reduce all of geometry to arithmetic [Bolzano, by Brown,JR] |
Full Idea: Bolzano if the father of 'arithmetization', which sought to found all of analysis on the concepts of arithmetic and to eliminate geometrical notions entirely (with logicism taking it a step further, by reducing arithmetic to logic). | |
From: report of Bernard Bolzano (Theory of Science (Wissenschaftslehre, 4 vols) [1837]) by James Robert Brown - Philosophy of Mathematics Ch. 3 | |
A reaction: Brown's book is a defence of geometrical diagrams against Bolzano's approach. Bolzano sounds like the modern heir of Pythagoras, if he thinks that space is essentially numerical. |
10856 | A truly infinite quantity does not need to be a variable [Bolzano] |
Full Idea: A truly infinite quantity (for example, the length of a straight line, unbounded in either direction) does not by any means need to be a variable. | |
From: Bernard Bolzano (Paradoxes of the Infinite [1846]), quoted by Brian Clegg - Infinity: Quest to Think the Unthinkable §10 | |
A reaction: This is an important idea, followed up by Cantor, which relegated to the sidelines the view of infinity as simply something that could increase without limit. Personally I like the old view, but there is something mathematically stable about infinity. |
9830 | Bolzano began the elimination of intuition, by proving something which seemed obvious [Bolzano, by Dummett] |
Full Idea: Bolzano began the process of eliminating intuition from analysis, by proving something apparently obvious (that as continuous function must be zero at some point). Proof reveals on what a theorem rests, and that it is not intuition. | |
From: report of Bernard Bolzano (Theory of Science (Wissenschaftslehre, 4 vols) [1837]) by Michael Dummett - Frege philosophy of mathematics Ch.6 | |
A reaction: Kant was the target of Bolzano's attack. Two responses might be to say that many other basic ideas are intuited but impossible to prove, or to say that proof itself depends on intuition, if you dig deep enough. |
17265 | Philosophical proofs in mathematics establish truths, and also show their grounds [Bolzano, by Correia/Schnieder] |
Full Idea: Mathematical proofs are philosophical in method if they do not only demonstrate that a certain mathematical truth holds but if they also disclose why it holds, that is, if they uncover its grounds. | |
From: report of Bernard Bolzano (Theory of Science (Wissenschaftslehre, 4 vols) [1837]) by Correia,F/Schnieder,B - Grounding: an opinionated introduction 2.3 | |
A reaction: I aim to defend the role of explanation in mathematics, but this says that this is only if the proofs are 'philosophical', which may be of no interest to mathematicians. Oh well, that's their loss. |
16062 | A necessary relation between fact-levels seems to be a further irreducible fact [Lynch/Glasgow] |
Full Idea: It seems unavoidable that the facts about logically necessary relations between levels of facts are themselves logically distinct further facts, irreducible to the microphysical facts. | |
From: Lynch,MP/Glasgow,JM (The Impossibility of Superdupervenience [2003], C) | |
A reaction: I'm beginning to think that rejecting every theory of reality that is proposed by carefully exposing some infinite regress hidden in it is a rather lazy way to do philosophy. Almost as bad as rejecting anything if it can't be defined. |
16061 | If some facts 'logically supervene' on some others, they just redescribe them, adding nothing [Lynch/Glasgow] |
Full Idea: Logical supervenience, restricted to individuals, seems to imply strong reduction. It is said that where the B-facts logically supervene on the A-facts, the B-facts simply re-describe what the A-facts describe, and the B-facts come along 'for free'. | |
From: Lynch,MP/Glasgow,JM (The Impossibility of Superdupervenience [2003], C) | |
A reaction: This seems to be taking 'logically' to mean 'analytically'. Presumably an entailment is logically supervenient on its premisses, and may therefore be very revealing, even if some people think such things are analytic. |
16060 | Nonreductive materialism says upper 'levels' depend on lower, but don't 'reduce' [Lynch/Glasgow] |
Full Idea: The root intuition behind nonreductive materialism is that reality is composed of ontologically distinct layers or levels. …The upper levels depend on the physical without reducing to it. | |
From: Lynch,MP/Glasgow,JM (The Impossibility of Superdupervenience [2003], B) | |
A reaction: A nice clear statement of a view which I take to be false. This relationship is the sort of thing that drives people fishing for an account of it to use the word 'supervenience', which just says two things seem to hang out together. Fluffy materialism. |
16064 | The hallmark of physicalism is that each causal power has a base causal power under it [Lynch/Glasgow] |
Full Idea: Jessica Wilson (1999) says what makes physicalist accounts different from emergentism etc. is that each individual causal power associated with a supervenient property is numerically identical with a causal power associated with its base property. | |
From: Lynch,MP/Glasgow,JM (The Impossibility of Superdupervenience [2003], n 11) | |
A reaction: Hence the key thought in so-called (serious, rather than self-evident) 'emergentism' is so-called 'downward causation', which I take to be an idle daydream. |
9185 | Bolzano wanted to avoid Kantian intuitions, and prove everything that could be proved [Bolzano, by Dummett] |
Full Idea: Bolzano was determined to expel Kantian intuition from analysis, and to prove from first principles anything that could be proved, no matter how obvious it might seem when thought of in geometrical terms. | |
From: report of Bernard Bolzano (Theory of Science (Wissenschaftslehre, 4 vols) [1837]) by Michael Dummett - The Philosophy of Mathematics 2.3 | |
A reaction: This is characteristic of the Enlightenment Project, well after the Enlightenment. It is a step towards Frege's attack on 'psychologism' in mathematics. The problem is that it led us into a spurious platonism. We live in troubled times. |
17073 | I simply reject evidence, if it is totally contrary to my web of belief [Smart] |
Full Idea: The simplest way of fitting the putative observed phenomena of telepathy or clairvoyance into my web of belief is to refuse to take them at face value. | |
From: J.J.C. Smart (Explanation - Opening Address [1990], p.07-8) | |
A reaction: Love it. It is very disconcerting for the sceptical naturalist to be faced with adamant claims that the paranormal has occurred, but my response is exactly the same as Smart's. I reject the reports, no matter how passionately they are asserted. |
17077 | The height of a flagpole could be fixed by its angle of shadow, but that would be very unusual [Smart] |
Full Idea: You could imagine a person using the angle from a theodolite to decide a suitable spot to cut the height of the flagpole, …but since such circumstances would be very unusual we naturally say the flagpole subtends the angle because of its height. | |
From: J.J.C. Smart (Explanation - Opening Address [1990], p.14) | |
A reaction: [compressed; he mentions Van Fraassen 1980:132-3 for a similar point] As a response this seems a bit lame, if the direction is fixed by what is 'usual'. I think the key point is that the direction of explanation is one way or the other, not both. |
17078 | Universe expansion explains the red shift, but not vice versa [Smart] |
Full Idea: The theory of the expansion of the universe renders the red shift no longer puzzling, whereas he expansion of the universe is hardly rendered less puzzling by facts about the red shift. | |
From: J.J.C. Smart (Explanation - Opening Address [1990], p.15) | |
A reaction: The direction of explanation is, I take it, made obvious by the direction of causation, with questions about what is 'puzzling' as mere side-effects. |
17061 | Explanation of a fact is fitting it into a system of beliefs [Smart] |
Full Idea: I want to characterise explanation of some fact as a matter of fitting belief in this fact into a system of beliefs. | |
From: J.J.C. Smart (Explanation - Opening Address [1990], p.02) | |
A reaction: Sounds good to me. Simple facts slot straight into daily beliefs, and deep obscure facts are explained when we hook them up to things we have already grasped. Quark theory fits into prior physics of forces, properties etc. |
17074 | Explanations are bad by fitting badly with a web of beliefs, or fitting well into a bad web [Smart] |
Full Idea: An explanation may be bad if it fits only into a bad web of belief. It can also be bad if it fits into a (possibly good) web of belief in a bad sort of way. | |
From: J.J.C. Smart (Explanation - Opening Address [1990], p.09) | |
A reaction: Nice. If you think someone has an absurd web of beliefs, then it counts against some belief (for you) if it fits beautifully into the other person's belief system. Judgement of coherence comes in at different levels. |
17076 | Deducing from laws is one possible way to achieve a coherent explanation [Smart] |
Full Idea: The Hempelian deductive-nomological model of explanation clearly fits in well with the notion of explanation in terms of coherence. One way of fitting a belief into a system is to show that it is deducible from other beliefs. | |
From: J.J.C. Smart (Explanation - Opening Address [1990], p.13) | |
A reaction: Smart goes on to reject the law-based deductive approach, for familiar reasons, but at least it has something in common with the Smart view of explanation, which is the one I like. |
17071 | An explanation is better if it also explains phenomena from a different field [Smart] |
Full Idea: One explanation will be a better explanation that another if it also explains a set of phenomena from a different field ('consilience'). | |
From: J.J.C. Smart (Explanation - Opening Address [1990], p.07) | |
A reaction: This would count as 'unexpected accommodation', rather than prediction. It is a nice addition to Lipton's comparison of mere accommodation versus prediction as criteria. It sounds like a strong criterion for a persuasive explanation. |
17062 | If scientific explanation is causal, that rules out mathematical explanation [Smart] |
Full Idea: I class mathematical explanation with scientific explanation. This would be resisted by those who, unlike me, regard the notion of causation as essential to scientific explanation. | |
From: J.J.C. Smart (Explanation - Opening Address [1990], p.02-3) | |
A reaction: I aim to champion mathematical explanation, in terms of axioms etc., so I am realising that my instinctive attraction to exclusively causal explanation won't do. What explanation needs is a direction of dependence. |
17075 | Scientific explanation tends to reduce things to the unfamiliar (not the familiar) [Smart] |
Full Idea: The history of science suggests that most often explanation is reduction to the unfamiliar. | |
From: J.J.C. Smart (Explanation - Opening Address [1990], p.11) | |
A reaction: Boyle was keen to reduce things to the familiar, but that was early days for science, and some nasty shocks were coming our way. What would Boyle make of quantum non-locality? |
22276 | Bolzano saw propositions as objective entities, existing independently of us [Bolzano, by Potter] |
Full Idea: Bolzano took the entities of which truth is predicated to be not propositions in the subjective sense but 'propositions-in-themselves' - objective entities existing independent of our apprehension. | |
From: report of Bernard Bolzano (Theory of Science (Wissenschaftslehre, 4 vols) [1837]) by Michael Potter - The Rise of Analytic Philosophy 1879-1930 02 'Emp' | |
A reaction: A serious mistake. Presumably the objective propositions are all true (or there would be endless infinities of them). So what is assessed in the case of error? Something other than the objective propositions! We assess these other things! |
17264 | Propositions are abstract structures of concepts, ready for judgement or assertion [Bolzano, by Correia/Schnieder] |
Full Idea: Bolzano conceived of propositions as abstract objects which are structured compounds of concepts and potential contents of judgements and assertions. | |
From: report of Bernard Bolzano (Theory of Science (Wissenschaftslehre, 4 vols) [1837]) by Correia,F/Schnieder,B - Grounding: an opinionated introduction 2.3 | |
A reaction: Personally I think of propositions as brain events, the constituents of thought about the world, but that needn't contradict the view of them as 'abstract'. |
12232 | A 'proposition' is the sense of a linguistic expression, and can be true or false [Bolzano] |
Full Idea: What I mean by 'propositions' is not what the grammarians call a proposition, namely the linguistic expression, but the mere sense of this expression, is what is meant by proposition in itself or object proposition. This sense can be true or false. | |
From: Bernard Bolzano (Theory of Science (Wissenschaftslehre, 4 vols) [1837], Pref?) | |
A reaction: This seems to be the origin of what we understand by 'proposition'. The disputes are over whether such things exists, and whether they are features of minds or features of the world (resembling facts). |
12233 | The ground of a pure conceptual truth is only in other conceptual truths [Bolzano] |
Full Idea: We can find the ground of a pure conceptual truth only in other conceptual truths. | |
From: Bernard Bolzano (Theory of Science (Wissenschaftslehre, 4 vols) [1837], Pref) | |
A reaction: Elsewhere he insists that these grounds must be in 'truths', and not just in the attributes of the concepts of involved. This conflicts with Kit Fine's view, that the concepts themselves are the source of conceptual truth and necessity. |
22405 | Negative utilitarianism implies that the world should be destroyed, to avoid future misery [Smart] |
Full Idea: The doctrine of negative utilitarianism (that we should concern ourselves with the minimisation of suffering, rather than the maximisation of happiness) ...means we should support a tyrant who explodes the world, to prevent infinite future misery. | |
From: J.J.C. Smart (Outline of a System of Utilitarianism [1973], 5) | |
A reaction: That only seems to imply that the negative utilitarian rule needs supplementary rules. We are too fond of looking for one single moral rule that guides everything. |
22404 | Any group interested in ethics must surely have a sentiment of generalised benevolence [Smart] |
Full Idea: A utilitarian can appeal to the sentiment of generalised benevolence, which is surely present in any group with whom it is profitable to discuss ethical questions. | |
From: J.J.C. Smart (Outline of a System of Utilitarianism [1973], I) | |
A reaction: But ethics is not intended only for those who are interested in ethics. If this is the basics of ethics, then we must leave the mafia to pursue its sordid activities without criticism. Their lack of sympathy seems to be their good fortune. |
14613 | Special relativity won't determine a preferred frame, but we can pick one externally [Smart] |
Full Idea: Though special relativity does not determine a preferred frame of reference, it does not rule out the possibility of a frame being determined from outside the theory. Perhaps we should prefer a frame where background radiation is equal in all directions. | |
From: J.J.C. Smart (The Tenseless Theory of Time [2008], 3) | |
A reaction: Of course this is a mere philosopher offering the escape clause, and not some Nobel-winning physicist, but I start from the assumption that this idea is plausible, and I am unmoved by the contempt for presentism among relativity geeks. |
17063 | Unlike Newton, Einstein's general theory explains the perihelion of Mercury [Smart] |
Full Idea: Newtonian celestial mechanics does not explain the advance of the perihelion of Mercury, while Einstein's general theory of relativity does. | |
From: J.J.C. Smart (Explanation - Opening Address [1990], p.03) | |
A reaction: A perfect example of why explanation is the central concept in science, and probably in all epistemological activity. The desire to know is the desire for an explanation. Once the explanation is obvious, we know. |
14615 | If time flows, then 'how fast does it flow?' is a tricky question [Smart] |
Full Idea: If it is said that time flows, then it seems that the question 'how fast does it flow?' is a devastating one for the A-theorist. | |
From: J.J.C. Smart (The Tenseless Theory of Time [2008], 5) | |
A reaction: This is one of the basic landmarks in any debate on time. Time can't be understood by analogy with anything else (such as a river) it seems. |
14614 | The past, present, future and tenses of A-theory are too weird, and should be analysed indexically [Smart] |
Full Idea: The main objections to the A-theory are due to the metaphysical mysteriousness of the A-theory ideas of past, present and future, and also tenses, and to the greater plausibility of analyzing them as indexicals. | |
From: J.J.C. Smart (The Tenseless Theory of Time [2008], 3) | |
A reaction: When it comes to time, every theory that has ever been though of is deeply weird, so the basic objection doesn't bother me. Analysing as indexicals just seems to be a technical way of denying reality to the present. |