96 ideas
| 17016 | Philosophy must abstract from the senses [Newton] |
| Full Idea: In philosophy abstraction from the senses is required. | |
| From: Isaac Newton (Principia Mathematica [1687], Def 8 Schol) | |
| A reaction: He particularly means 'natural philosophy' (i.e. science), but there is no real distinction in Newton's time, and I would say this remark is true of modern philosophy. |
| 4098 | The theory of descriptions supports internalism, since they are thinkable when the object is non-existent [Crane] |
| Full Idea: The theory of descriptions gives a model of internalist intentionality, in that it describes cases where the thinkability of a belief does not depend on the existence of a specific object. | |
| From: Tim Crane (Elements of Mind [2001], 4.36) | |
| A reaction: So what do externalists say about the theory? Surely a reference to 'water' can't entail the existence of water? |
| 18079 | Newton developed a kinematic approach to geometry [Newton, by Kitcher] |
| Full Idea: The reduction of the problems of tangents, normals, curvature, maxima and minima were effected by Newton's kinematic approach to geometry. | |
| From: report of Isaac Newton (Principia Mathematica [1687]) by Philip Kitcher - The Nature of Mathematical Knowledge 10.1 | |
| A reaction: This approach apparently contrasts with that of Leibniz. |
| 13152 | We can talk of 'innumerable number', about the infinite points on a line [Newton] |
| Full Idea: If any man shall take the words number and sum in a larger sense, to understand things which are numberless and sumless (such as the infinite points on a line), I could allow him the contradictious phrase 'innumerable number' without absurdity. | |
| From: Isaac Newton (Letters to Bentley [1692], 1693.02.25) | |
| A reaction: [compressed] I take the key point here to be the phrase of taking number 'in a larger sense'. Like the word 'atom' in physics, the word 'number' retains its traditional reference, but has considerably shifted its scope. Amateurs must live with this. |
| 13151 | Not all infinites are equal [Newton] |
| Full Idea: It is an error that all infinites are equal. | |
| From: Isaac Newton (Letters to Bentley [1692], 1693.01.17) | |
| A reaction: There follows a discussion of the mathematicians' view of infinity. Cantor was not the first to notice that there is more than one sort of of infinity. |
| 18082 | Quantities and ratios which continually converge will eventually become equal [Newton] |
| Full Idea: Quantities and the ratios of quantities, which in any finite time converge continually to equality, and, before the end of that time approach nearer to one another by any given difference become ultimately equal. | |
| From: Isaac Newton (Principia Mathematica [1687], Lemma 1), quoted by Philip Kitcher - The Nature of Mathematical Knowledge 10.2 | |
| A reaction: Kitcher observes that, although Newton relies on infinitesimals, this quotation expresses something close to the later idea of a 'limit'. |
| 13007 | Archimedes defined a straight line as the shortest distance between two points [Archimedes, by Leibniz] |
| Full Idea: Archimedes gave a sort of definition of 'straight line' when he said it is the shortest line between two points. | |
| From: report of Archimedes (fragments/reports [c.240 BCE]) by Gottfried Leibniz - New Essays on Human Understanding 4.13 | |
| A reaction: Commentators observe that this reduces the purity of the original Euclidean axioms, because it involves distance and measurement, which are absent from the purest geometry. |
| 17783 | A number is not a multitude, but a unified ratio between quantities [Newton] |
| Full Idea: By a Number we understand not so much a Multitude of Unities, as the abstracted Ratio of any Quantity to another Quantity of the same Kind, which we take for unity. | |
| From: Isaac Newton (Universal Arithmetick [1669]), quoted by John Mayberry - What Required for Foundation for Maths? p.407-2 | |
| A reaction: This needs a metaphysics of 'kinds' (since lines can't have ratios with solids). Presumably Newton wants the real numbers to be more basic than the natural numbers. This is the transition from Greek to modern. |
| 4077 | Aesthetic properties of thing supervene on their physical properties [Crane] |
| Full Idea: It is sometimes said that the aesthetic properties of a thing supervene on its physical properties. | |
| From: Tim Crane (Elements of Mind [2001], 2.16) | |
| A reaction: A confusing example, as aesthetic properties only exist if there is an observer. Is 'supervenience' just an empty locution which tries to avoid reduction? |
| 4078 | Constitution (as in a statue constituted by its marble) is supervenience without identity [Crane] |
| Full Idea: A statue is constituted by the marble that makes it up. It is plausible to say that constitution is not the same as identity - since identity is symmetrical and identity is not - but nonetheless constitution is a supervenience relation. | |
| From: Tim Crane (Elements of Mind [2001], 2.16) | |
| A reaction: So what makes it a statue, as opposed to a piece of marble? It may well be an abstraction which only exists relative to observers. |
| 8386 | Events are picked out by descriptions, and facts by whole sentences [Crane] |
| Full Idea: Events are picked out using descriptions ('The death of Caesar'), while facts are picked out using whole sentences ('Caesar died'). | |
| From: Tim Crane (Causation [1995], 1.4.2) | |
| A reaction: Useful, and interesting. He mentions that Kim's usage doesn't agree with this. For analysis purposes, this means that an event is a more minimal item than a fact, and many facts will contain events as components. |
| 4082 | The distinction between 'resultant' properties (weight) and 'emergent' properties is a bit vague [Crane] |
| Full Idea: The distinction between 'resultant' properties like weight, and 'emergent' properties like colour, seems intuitive enough, but on examination it is very hard to make precise. | |
| From: Tim Crane (Elements of Mind [2001], 2.18) | |
| A reaction: It is no coincidence that the examples are of primary and secondary qualities. If 'the physical entails the mental' then all mental properties are resultant. |
| 4083 | If mental properties are emergent they add a new type of causation, and physics is not complete [Crane] |
| Full Idea: Whatever the causal process is, it remains true that if emergentism is true, the completeness of physics is false; there are some effects which would not have come about if mental things were absent from the world. | |
| From: Tim Crane (Elements of Mind [2001], 2.18) | |
| A reaction: Emergentism looks to me like an incoherent concept, unless it is another word for dualism. |
| 17011 | I suspect that each particle of bodies has attractive or repelling forces [Newton] |
| Full Idea: Many things lead me to a suspicion that all phenomena may depend on certain forces by which the particles of bodies, by causes not yet known, either are impelled toward one another and cohere in regular figures,or are repelled from one another and recede. | |
| From: Isaac Newton (Principia Mathematica [1687], Pref) | |
| A reaction: For Newton, forces are not just abstractions that are convenient for mathematics, but realities which I would say are best described as 'powers'. |
| 4079 | Properties are causes [Crane] |
| Full Idea: Properties are causes. | |
| From: Tim Crane (Elements of Mind [2001], 2.17) | |
| A reaction: We can't detect properties if they lack causal powers. This may be a deep confusion. Properties are what make causal powers possible, but that isn't what properties are? |
| 17028 | Particles mutually attract, and cohere at short distances [Newton] |
| Full Idea: The particles of bodies attract one another at very small distances and cohere when they become contiguous. | |
| From: Isaac Newton (Principia Mathematica [1687], Bk 3 Gen Schol) | |
| A reaction: This is the sort of account of unity which has to be given in the corpuscular view of things, once substantial forms are given up. What is missing here is the structure of the thing. A lump of dirt is as unified as a cat in this story. |
| 4068 | Traditional substance is separate from properties and capable of independent existence [Crane] |
| Full Idea: The traditional concept of substance says substances bear properties which are distinct from them, and substances are capable of independent existence. | |
| From: Tim Crane (Elements of Mind [2001], 2.9) | |
| A reaction: Put like that, it sounds ridiculous as a physical theory. It is hard to dislodge substance, though, from a priori human metaphysics. |
| 17014 | The place of a thing is the sum of the places of its parts [Newton] |
| Full Idea: The place of a whole is the same as the sum of the places of the parts, and is therefore internal and in the whole body. | |
| From: Isaac Newton (Principia Mathematica [1687], Def 8 Schol) | |
| A reaction: Note that Newton is talking of the sums of places, and deriving them from the parts. This is the mereology of space. |
| 4096 | Maybe beliefs don't need to be conscious, if you are not conscious of the beliefs guiding your actions [Crane] |
| Full Idea: The beliefs that are currently guiding your actions do not need to be in your stream of consciousness, which suggests that beliefs do not need to be conscious at all. | |
| From: Tim Crane (Elements of Mind [2001], 4.31) | |
| A reaction: Too bold, I think. Presumably this would eliminate all the other propositional attitudes from consciousness. There would only be qualia left! |
| 4097 | Maybe there are two kinds of belief - 'de re' beliefs and 'de dicto' beliefs [Crane] |
| Full Idea: Some philosophers have claimed that there are two kinds of belief, 'de re' belief and 'de dicto' belief. | |
| From: Tim Crane (Elements of Mind [2001], 4.35) | |
| A reaction: Interesting, though it may only distinguish two objects of belief, not two types. Internalist and externalist views are implied. |
| 4093 | Many cases of knowing how can be expressed in propositional terms (like how to get somewhere) [Crane] |
| Full Idea: There are plenty of cases of knowing how to do something, where that knowledge can also be expressed - without remainder, as it were - in propositional terms (such as knowing how to get to the Albert Hall). | |
| From: Tim Crane (Elements of Mind [2001], 3.28) | |
| A reaction: Presumably all knowing how could be expressed propositionally by God. |
| 4108 | Phenol-thio-urea tastes bitter to three-quarters of people, but to the rest it is tasteless, so which is it? [Crane] |
| Full Idea: Phenol-thio-urea tastes bitter to three-quarters of people, but to the rest it is tasteless. Is it really bitter, or really tasteless? | |
| From: Tim Crane (Elements of Mind [2001], 5.44) | |
| A reaction: A nice reinforcement of a classic Greek question. Good support for the primary/secondary distinction. Common sense, really. |
| 4105 | The traditional supports for the sense datum theory were seeing double and specks before one's eyes [Crane] |
| Full Idea: The traditional examples used to support the sense datum theory were seeing double and specks before one's eyes. | |
| From: Tim Crane (Elements of Mind [2001], 5.43) | |
| A reaction: Presumably, though, direct realists can move one eye, or having something wrong with a retina. |
| 4104 | One can taste that the wine is sour, and one can also taste the sourness of the wine [Crane] |
| Full Idea: One can taste that the wine is sour, and one can also taste the sourness of the wine. | |
| From: Tim Crane (Elements of Mind [2001], 5.42) | |
| A reaction: …so sense data are optional? We create sense data by objectifying them, but animals just taste the wine, and are direct realists. Tasting the sourness seems to be a case of abstraction. |
| 4101 | If we smell something we are aware of the smell separately, but we don't perceive a 'look' when we see [Crane] |
| Full Idea: Visual perception seems to differ from some of the other senses; when we become aware of burning toast, we become aware of the smell, ...but we don't see a garden by seeing a 'look' of the garden. | |
| From: Tim Crane (Elements of Mind [2001], 5.40) | |
| A reaction: Interesting. Do blind people transfer this more direct perception to a different sense (e.g. the one they rely on most)? |
| 4102 | The problems of perception disappear if it is a relation to an intentional state, not to an object or sense datum [Crane] |
| Full Idea: The solution to the problem of perception is to deny that it is related to real objects (things or sense-data); rather, perception is an intentional state (with a subject, mode and content), a relation to the intentional content. | |
| From: Tim Crane (Elements of Mind [2001], 5.42) | |
| A reaction: Not clear. This definition makes it sound like a propositional attitude. |
| 4109 | If perception is much richer than our powers of description, this suggests that it is non-conceptual [Crane] |
| Full Idea: The richness in information of perceptual experience outruns our modes of description of it, which has led some philosophers to claim that the content of perceptual experience is non-conceptual. | |
| From: Tim Crane (Elements of Mind [2001], 5.45) | |
| A reaction: It certainly implies that it can't be entirely conceptual, but it still may be that in humans concepts are always involved. Not when I'm waking up in the morning, though. |
| 4103 | The adverbial theory of perceptions says it is the experiences which have properties, not the objects [Crane] |
| Full Idea: The Adverbial Theory of perception holds that the predicates which other theories take as picking out the properties of objects are really adverbs of the perceptual verb; ..instead of strange objects, we just have properties of experiences. | |
| From: Tim Crane (Elements of Mind [2001], 5.42) | |
| A reaction: Promising. It fits secondary qualities all right, but what about primary? I 'see bluely', but can I 'see squarely'? |
| 4065 | Is knowledge just a state of mind, or does it also involve the existence of external things? [Crane] |
| Full Idea: It is controversial whether knowledge is a state of mind, or a composite state involving a thought about something, plus its existence. | |
| From: Tim Crane (Elements of Mind [2001], 1.5) | |
| A reaction: Pinpoints the internalism/externalism problem. Knowledge is a special type of belief (but maybe belief with external links!). Tricky. I vote for internalism. |
| 17546 | If you changed one of Newton's concepts you would destroy his whole system [Heisenberg on Newton] |
| Full Idea: The connection between the different concept in [Newton's] system is so close that one could generally not change any one of the concepts without destroying the whole system | |
| From: comment on Isaac Newton (Principia Mathematica [1687]) by Werner Heisenberg - Physics and Philosophy 06 | |
| A reaction: This holistic situation would seem to count against Newton's system, rather than for it. A good system should depend on nature, not on other parts of the system. Compare changing a rule of chess. |
| 17027 | Science deduces propositions from phenomena, and generalises them by induction [Newton] |
| Full Idea: In experimental philosophy, propositions are deduced from the phenomena and are made general by induction. | |
| From: Isaac Newton (Principia Mathematica [1687], Bk 3 Gen Schol) | |
| A reaction: Sounds easy, but generalising by induction requires all sorts of assumptions about the stability of natural kinds. Since the kinds are only arrived at by induction, it is not easy to give a proper account here. |
| 17022 | We should admit only enough causes to explain a phenomenon, and no more [Newton] |
| Full Idea: No more causes of natural things should be admitted than are both true and sufficient to explain the phenomena. …For nature does nothing in vain, …and nature is simple and does not indulge in the luxury of superfluous causes. | |
| From: Isaac Newton (Principia Mathematica [1687], Bk 3 Rule 1) | |
| A reaction: This emphasises that Ockham's Razor is a rule for physical explanation, and not just one for abstract theories. This is something like Van Fraassen's 'empirical adequacy'. |
| 17021 | Natural effects of the same kind should be assumed to have the same causes [Newton] |
| Full Idea: The causes assigned to natural effects of the same kind must be, so far as possible, the same. For example, the cause of respiration in man and beast. | |
| From: Isaac Newton (Principia Mathematica [1687], Bk 3 Rule 2) | |
| A reaction: It is impossible to rule out identical effects from differing causes, but explanation gets much more exciting (because wide-ranging) if Newton's rule is assumed. |
| 17026 | From the phenomena, I can't deduce the reason for the properties of gravity [Newton] |
| Full Idea: I have not as yet been able to deduce from the phenomena the reason for the properties of gravity. | |
| From: Isaac Newton (Principia Mathematica [1687], Bk 3 Gen Schol) | |
| A reaction: I take it that giving the reasons for the properties of gravity would be an essentialist explanation. I am struck by the fact that the recent discovery of the Higgs Boson appears to give us a reason why things have mass (i.e. what causes mass). |
| 4092 | The core of the consciousness problem is the case of Mary, zombies, and the Hard Question [Crane] |
| Full Idea: The three arguments that have been used to articulate the problem of consciousness are the knowledge argument ('Mary'), the possibility of 'zombies' (creatures like us but lacking phenomenal consciousness), and the explanatory gap (the Hard Question). | |
| From: Tim Crane (Elements of Mind [2001], 3.26) | |
| A reaction: All of these push towards the implausible claim that there could never be a physical explanation of why we experience things. Zombies are impossible, in my opinion. |
| 4087 | Intentionalism does not require that all mental states be propositional attitudes [Crane] |
| Full Idea: Intentionalism (the doctrine that all mental states are intentional) need not be the thesis that all mental states are propositional attitudes. | |
| From: Tim Crane (Elements of Mind [2001], 3.22) | |
| A reaction: This points to the requirement for an intentionalist to prove that so-called 'qualia' states are essentially intentional, which is not implausible. |
| 4095 | Object-directed attitudes like love are just as significant as propositional attitudes [Crane] |
| Full Idea: Love, hate, and the other object-directed attitudes have as much of a role in explaining behaviour as the propositional attitudes. | |
| From: Tim Crane (Elements of Mind [2001], 4.34) | |
| A reaction: A good clarification of the range of intentional states. Objects seem to be external, where propositions are clearly internal. |
| 4106 | If someone removes their glasses the content of experience remains, but the quality changes [Crane] |
| Full Idea: There is a phenomenal difference between a short-sighted person wearing glasses and not; they do not judge that the world is different, but the properties of the experience (the qualia) have changed. | |
| From: Tim Crane (Elements of Mind [2001], 5.43) | |
| A reaction: Could be challenged. If a notice becomes unreadable, that is more than the qualia changing. |
| 4089 | Pains have a region of the body as their intentional content, not some pain object [Crane] |
| Full Idea: The intentional object of a pain-state is a part or region of the body, not a pain-object. | |
| From: Tim Crane (Elements of Mind [2001], 3.24) | |
| A reaction: Plausible. Has anyone ever suffered from pain without some sense of what part of the body is actually in pain? |
| 4090 | Weak intentionalism says qualia are extra properties; strong intentionalism says they are intentional [Crane] |
| Full Idea: Weak intentionalism says all mental states are intentional, but qualia are higher-order properties of these states. ..Strong intentionalists say the phenomenal character of a sensation consists purely in that state's intentionality. | |
| From: Tim Crane (Elements of Mind [2001], 3.25) | |
| A reaction: The weak version sounds better. Asking 'how could a thought have a quality of experience just by being about something?' is a restatement of the traditional problem, which won't go away. The Hard Question. |
| 4107 | With inverted qualia a person's experiences would change, but their beliefs remain the same [Crane] |
| Full Idea: The right thing to say about inverted qualia is that the person's experiences are different from other people's, but their beliefs are the same. | |
| From: Tim Crane (Elements of Mind [2001], 5.44) | |
| A reaction: Right - which reinforces the idea that all beliefs are the result of judgement, and none come directly from perception. |
| 4069 | Descartes did not think of minds as made of a substance, because they are not divisible [Crane] |
| Full Idea: It would be wrong to represent Descartes' view as the idea that bodies are made of one kind of stuff and minds of another; he did not think minds are made of stuff at all, because then they would be divisible. | |
| From: Tim Crane (Elements of Mind [2001], 2.10) | |
| A reaction: I'm not convinced. It could be an indivisible substance. Without a mental substance, Descartes may have to say the mind is an abstraction, perhaps a pattern of Platonic forms. |
| 4074 | Functionalism defines mental states by their causal properties, which rules out epiphenomenalism [Crane] |
| Full Idea: Functionalism holds that it is in the nature of certain mental states to have certain effects; therefore there can be no mental epiphenomena. | |
| From: Tim Crane (Elements of Mind [2001], 2.14) | |
| A reaction: I strongly resist the idea that a thing's identity is its function. Functionalism may not say that. Mind is an abstraction referring to a causal nexus of unknowable components. |
| 4091 | The problems of misrepresentation and error have dogged physicalist reductions of intentionality [Crane] |
| Full Idea: The fundamental problems of misrepresentation and error have dogged physicalist reductions of intentionality. | |
| From: Tim Crane (Elements of Mind [2001], 3.26) | |
| A reaction: If footprints or tree-rings are the model for reductions of intentionality, there doesn't seem much scope in them for giving false information, except by some freak event. |
| 4070 | Properties dualism says mental properties are distinct from physical, despite a single underlying substance [Crane] |
| Full Idea: According to property dualism, mental properties are distinct from physical properties, even though they are properties of one substance. | |
| From: Tim Crane (Elements of Mind [2001], 2.10) | |
| A reaction: Two properties may be phenomenologically different (transparent and magnetic), but that doesn't put them in different ontological categories. |
| 4084 | Non-reductive physicalism seeks an explanation of supervenience, but emergentists accept it as basic [Crane] |
| Full Idea: While the non-reductive physicalist believes that mental/physical supervenience must be explained, the emergentist is willing to accept it as a fact of nature. | |
| From: Tim Crane (Elements of Mind [2001], 2.18) | |
| A reaction: A good reason not to be an emergentist. No philosopher should abandon the principle of sufficient reason. |
| 4080 | If mental supervenes on the physical, then every physical cause will be accompanied by a mental one [Crane] |
| Full Idea: If the mental supervenes on the physical, then whenever a physical cause brings about some effect, a mental cause comes along for the ride. | |
| From: Tim Crane (Elements of Mind [2001], 2.17) | |
| A reaction: This is why supervenience seems to imply epiphenomenalism. The very concept of supervenience is dubious. |
| 4075 | Identity theory is either of particular events, or of properties, depending on your theory of causation [Crane] |
| Full Idea: If causation concerns events, then we have an identity theory of mental and physical events (particulars) [Davidson]. If causation is by properties, then it is mental and physical properties which are identical [Lewis and Armstrong]. | |
| From: Tim Crane (Elements of Mind [2001], 2.14) | |
| A reaction: Events are tokens, and properties are types. Tricky. Events are dynamic, but properties can be static. |
| 4085 | Physicalism may be the source of the mind-body problem, rather than its solution [Crane] |
| Full Idea: Physicalism may be the source of the mind-body problem, rather than its solution. | |
| From: Tim Crane (Elements of Mind [2001], 2.19) | |
| A reaction: Certainly if the physical is seen as just a pile of atoms, it is hard to see how they could ever think (see idea 1909). |
| 4073 | Overdetermination occurs if two events cause an effect, when each would have caused it alone [Crane] |
| Full Idea: Causal overdetermination is when an effect has more than one cause, and each event would have caused the effect if the other one had not done so. | |
| From: Tim Crane (Elements of Mind [2001], 2.13) | |
| A reaction: Overdetermination is a symptom that an explanation is questionable, but it can occur. Two strong people can join to push over a light hatstand. |
| 4072 | The completeness of physics must be an essential component of any physicalist view of mind [Crane] |
| Full Idea: I claim that the completeness of physics must be an essential component of any physicalist view of mind. | |
| From: Tim Crane (Elements of Mind [2001], 2.12) | |
| A reaction: He does not convince me of this. The mind may be within physics, but why should we say a priori that no exceptions to physical law will ever be discovered. Crane is setting up straw men. |
| 4094 | Experience teaches us propositions, because we can reason about our phenomenal experience [Crane] |
| Full Idea: In experience we learn propositions, since someone can reason using the sentence 'Red looks like this' (e.g. 'If red looks like this, then either it looks like this to dogs or it doesn't'). | |
| From: Tim Crane (Elements of Mind [2001], 3.28) | |
| A reaction: The fact that we can create propositions about experiences doesn't prove that experience is inherently propositional. |
| 4100 | The Twin Earth argument depends on reference being determined by content, which may be false. [Crane] |
| Full Idea: The Twin Earth argument does not refute internalism, since it depends on the 'Content-Determines-Reference' principle, which internalists can reject. | |
| From: Tim Crane (Elements of Mind [2001], 4.37) | |
| A reaction: The idea is that content should be understood in a context (e.g. on a particular planet). Indexicals count against a totally narrow view of content (Twins thinking 'I am here'). |
| 4067 | Broad content entails the existence of the object of the thought [Crane] |
| Full Idea: If a mental state is broad, then the existence of the mental state entails the existence of its object. | |
| From: Tim Crane (Elements of Mind [2001], 1.7) | |
| A reaction: Hence thinking of non-existent things like unicorns is problematic for externalists. However, externalists can think about numbers or Platonic ideals. |
| 4063 | In intensional contexts, truth depends on how extensions are conceived. [Crane] |
| Full Idea: Intensional contexts are those where truth or falsehood depends on the way the extensions are conceived. | |
| From: Tim Crane (Elements of Mind [2001], 1.4) | |
| A reaction: An important distinction for anyone defending an internalist view of concepts or of knowledge |
| 6421 | Newton's four fundamentals are: space, time, matter and force [Newton, by Russell] |
| Full Idea: Newton works with four fundamental concepts: space, time, matter and force. | |
| From: report of Isaac Newton (Principia Mathematica [1687]) by Bertrand Russell - My Philosophical Development Ch.2 | |
| A reaction: The ontological challenge is to reduce these in number, presumably. They are, notoriously, defined in terms of one another. |
| 13470 | Mass is central to matter [Newton, by Hart,WD] |
| Full Idea: For Newton, mass is central to matter. | |
| From: report of Isaac Newton (Principia Mathematica [1687]) by William D. Hart - The Evolution of Logic 2 | |
| A reaction: On reading this, I realise that this is the concept of matter I have grown up with, one which makes it very hard to grasp what the Greeks were thinking of when they referred to matter [hule]. |
| 17020 | An attraction of a body is the sum of the forces of their particles [Newton] |
| Full Idea: The attractions of the bodies must be reckoned by assigning proper forces to their individual particles and then taking the sums of those forces. | |
| From: Isaac Newton (Principia Mathematica [1687], 1.II.Schol) | |
| A reaction: This is using the parts of bodies to give fundamental explanations, rather than invoking substantial forms. The parts need not be atoms. |
| 23012 | Newtonian causation is changes of motion resulting from collisions [Newton, by Baron/Miller] |
| Full Idea: In the Newtonian mechanistic theory of causation, ….something causes a result when it brings about a change of motion. …Causation is a matter of things bumping into one another. | |
| From: report of Isaac Newton (Principia Mathematica [1687]) by Baron,S/Miller,K - Intro to the Philosophy of Time 6.2.1 | |
| A reaction: This seems to need impenetrability and elasticity as primitives (which is partly what Leibniz's monads are meant to explain). The authors observe that much causation is the result of existences and qualities, rather than motions. |
| 4071 | Causation can be seen in counterfactual terms, or as increased probability, or as energy flow [Crane] |
| Full Idea: A theory of causation might say 'If A had not existed, B would not have existed' (counterfactual theory), or 'B is more likely if A occurs' (probabilistic), or 'energy flows from A to B'. | |
| From: Tim Crane (Elements of Mind [2001], 2.11) | |
| A reaction: As always, it is vital to separate epistemology from ontology. Energy won't cover agents. Whisper "Fire!" in a theatre. |
| 8387 | A cause has its effects in virtue of its properties [Crane] |
| Full Idea: Some philosophers say that a cause has its effects in virtue of its properties. | |
| From: Tim Crane (Causation [1995], 1.4.2) | |
| A reaction: The trouble with this approach, I think, is that it encourages us to invent dubious properties, because every explanation of an effect will require one. Dormative properties, for example, are ascribed to sleeping pills. |
| 4076 | Causes are properties, not events, because properties are what make a difference in a situation [Crane] |
| Full Idea: My view is that causes are properties (not events); when we look for causes, we look for the aspect of a situation which made a difference, and aspects are properties or qualities. | |
| From: Tim Crane (Elements of Mind [2001], 2.14) | |
| A reaction: He is talking about explanations, which may not be causes, or at least they have a different emphasis. Don't events 'make a difference'? Events are ontologically weird |
| 8384 | The regularity theory explains a causal event by other items than the two that are involved [Crane] |
| Full Idea: An unsatisfactory aspect of the regularity thesis is that it explains why this A caused this B in terms of facts about things other that this A and this B. But we want to know what it is about this A and this B that makes one the cause of the other? | |
| From: Tim Crane (Causation [1995], 1.3) | |
| A reaction: Well said. This is the failing of any attempt to define things by their relationships (e.g. functional definitions). Hume, of course, was only relying on regularity because when he focused on the actual A and B, they had no helpful experiences to offer. |
| 15863 | The principles of my treatise are designed to fit with a belief in God [Newton] |
| Full Idea: When I wrote my treatise about our system, I had an eye upon such principles as might work with considering men, for the belief of a deity. | |
| From: Isaac Newton (Letters to Bentley [1692], 1692.12.10) | |
| A reaction: Harré quotes this, and it shows that the rather passive view of nature Newton developed was to be supplemented by the active power of God. Without God, we need a more active view of nature. |
| 16746 | Principles of things are not hidden features of forms, but the laws by which they were formed [Newton] |
| Full Idea: The (active) principles I consider not as occult qualities, supposed to result from the specific forms of things, but as general laws of nature, by which the things themselves are formed. | |
| From: Isaac Newton (Queries to the 'Opticks' [1721], q 31), quoted by Robert Pasnau - Metaphysical Themes 1274-1671 23.6 | |
| A reaction: This is the external, 'imposed' view of laws (with the matter passive) at its most persuasive. If laws arise out the stuff (as I prefer to think), what principles went into the formulation of the stuff? |
| 8340 | I do not pretend to know the cause of gravity [Newton] |
| Full Idea: You sometimes speak of gravity as essential and inherent in matter. Pray do no ascribe that notion to me; for the cause of gravity is what I do not pretend to know. | |
| From: Isaac Newton (Letters to Bentley [1692], 1693.01.17) | |
| A reaction: I take science to be a two-stage operation - first we discern the regularities, and then we explain them. Evolution was spotted, then explained by Darwin. Cancer from cigarettes was spotted, but hasn't been explained. Regularity is the beginning. |
| 17008 | You have discovered that elliptical orbits result just from gravitation and planetary movement [Newton, by Leibniz] |
| Full Idea: You have made the astonishing discovery that Kepler's ellipses result simply from the conception of attraction or gravitation and passage in a planet. | |
| From: report of Isaac Newton (Principia Mathematica [1687]) by Gottfried Leibniz - Letter to Newton 1693.03.07 | |
| A reaction: I quote this to show that Newton made 'an astonishing discovery' of a connection in nature, and did not merely produce an equation which described a pattern of behaviour. The simple equation is the proof of the connection. |
| 17010 | We have given up substantial forms, and now aim for mathematical laws [Newton] |
| Full Idea: The moderns - rejecting substantial forms and occult qualities - have undertaken to reduce the phenomena of nature to mathematical laws. | |
| From: Isaac Newton (Principia Mathematica [1687], Preface) | |
| A reaction: This is the simplest statement of the apparent anti-Aristotelian revolution in the seventeenth century. |
| 17023 | I am not saying gravity is essential to bodies [Newton] |
| Full Idea: I am by no means asserting that gravity is essential to bodies. | |
| From: Isaac Newton (Principia Mathematica [1687], Bk 3 Rule 3) | |
| A reaction: Notice that in Idea 17009 he does not rule out gravity being essential to bodies. This is Newton's intellectual modesty (for which he is not famous). |
| 17009 | I won't object if someone shows that gravity consistently arises from the action of matter [Newton] |
| Full Idea: If someone explains gravity along with all its laws by the action of some subtle matter, and shows that the motion of the planets and comets will not be disturbed by this matter, I shall be far from objecting. | |
| From: Isaac Newton (Letters to Leibniz 1 [1693], 1693.10.16) | |
| A reaction: Important if you think that Newton is the hero of the descriptive regularity theory of laws. Newton probably thought laws came from God, but he wouldn't object to Leibniz's view, that God planted the laws within the matter. |
| 13150 | The motions of the planets could only derive from an intelligent agent [Newton] |
| Full Idea: The motions which the planets now have could not spring from any natural cause alone, but were impressed by an intelligent agent. | |
| From: Isaac Newton (Letters to Bentley [1692], 1692.12.10) | |
| A reaction: He is writing to a cleric, but seems to be quite sincere about this. Elsewhere he just says he doesn't know what causes gravity. |
| 12178 | That gravity should be innate and essential to matter is absurd [Newton] |
| Full Idea: That gravity should be innate, inherent and essential to matter ...is to me so great an absurdity that I believe no man who has in philosophical matters a competent faculty of thinking can ever fall into it. | |
| From: Isaac Newton (Letters to Bentley [1692], 1693.02.25) | |
| A reaction: He is replying to some sermons, and he pays vague lip service to a possible divine force. Nevertheless, this is thoroughgoing anti-essentialism, and he talks of external 'laws' in the next sentence. Newton still sought the cause of gravity. |
| 15866 | Newton reclassified vertical motion as violent, and unconstrained horizontal motion as natural [Newton, by Harré] |
| Full Idea: Following Kepler, Newton assumed a law of universal gravitation, thus reclassifying free fall as a violent motion and, with his First Law, fixing horizontal motion in the absence of constraints as natural | |
| From: report of Isaac Newton (Principia Mathematica [1687]) by Rom Harré - Laws of Nature 1 | |
| A reaction: This is in opposition to the Aristotelian view, where the downward motion of physical objects is their natural motion. |
| 15958 | Inertia rejects the Aristotelian idea of things having natural states, to which they return [Newton, by Alexander,P] |
| Full Idea: Newton's principle of inertia implies a rejection of the Aristotelian idea of natural states to which things naturally return. | |
| From: report of Isaac Newton (Principia Mathematica [1687]) by Peter Alexander - Ideas, Qualities and Corpuscles 02.3 | |
| A reaction: I think we can safely say that Aristotle was wrong about this. Aristotle made too much (such as the gravity acting on a thing) intrinsic to the bodies, when the whole context must be seen. |
| 17017 | 1: Bodies rest, or move in straight lines, unless acted on by forces [Newton] |
| Full Idea: Law 1: Every body perseveres in its state of being at rest or of moving uniformly straight forward, except insofar as it is compelled to change its state by forces impressed. | |
| From: Isaac Newton (Principia Mathematica [1687], Axioms) | |
| A reaction: This is the new concept of inertia, which revolutionises the picture. Motion itself, which was a profound puzzle for the Greeks, ceases to be a problem by being axiomatised. It is now acceleration which is the the problem. |
| 17019 | 3: All actions of bodies have an equal and opposite reaction [Newton] |
| Full Idea: Law 3: To any action there is always an opposite and equal reaction; in other words, the action of two bodies upon each other are always equal and always opposite in direction. | |
| From: Isaac Newton (Principia Mathematica [1687], Axioms) | |
| A reaction: Is this still true if one body is dented by the impact and the other one isn't? What counts as a 'body'? |
| 20968 | Newton's Third Law implies the conservation of momentum [Newton, by Papineau] |
| Full Idea: Newton's Third Law implies the conservation of momentum, because 'action and reaction' are always equal. | |
| From: report of Isaac Newton (Principia Mathematica [1687]) by David Papineau - Thinking about Consciousness App 3 | |
| A reaction: That is, the Third Law implies the First Law (which is the Law of Momentum). |
| 17018 | 2: Change of motion is proportional to the force [Newton] |
| Full Idea: Law 2: A change in motion is proportional to the motive force impressed and takes place along the straight line in which that force is impressed. | |
| From: Isaac Newton (Principia Mathematica [1687], Axioms) | |
| A reaction: This gives the equation 'force = mass x acceleration', where the mass is the constant needed for the equation of proportion. Effectively mass is just the value of a proportion. |
| 17547 | Newton's idea of force acting over a long distance was very strange [Heisenberg on Newton] |
| Full Idea: Newton introduced a very new and strange hypothesis by assuming a force that acted over a long distance. | |
| From: comment on Isaac Newton (Principia Mathematica [1687]) by Werner Heisenberg - Physics and Philosophy 06 | |
| A reaction: Why would a force that acted over a short distance be any less mysterious? |
| 20966 | Newton introduced forces other than by contact [Newton, by Papineau] |
| Full Idea: Newton allowed forces other than impact. All the earlier proponents of 'mechanical philosophy' took it as given that all physical action is by contact. ...He thought of 'impressed force' - disembodied entities acting from outside a body. | |
| From: report of Isaac Newton (Principia Mathematica [1687]) by David Papineau - Thinking about Consciousness App 3 | |
| A reaction: This is 'action at a distance', which was as bewildering then as quantum theory is now. Newton had a divinity to impose laws of nature from the outside. In some ways we have moved back to the old view, with the actions of bosons and fields. |
| 20967 | Newton's laws cover the effects of forces, but not their causes [Newton, by Papineau] |
| Full Idea: Newton has a general law about the effects of his forces, ...but there is no corresponding general principle about the causes of such forces. | |
| From: report of Isaac Newton (Principia Mathematica [1687]) by David Papineau - Thinking about Consciousness App 3 | |
| A reaction: I'm not sure that Einstein gives a cause of gravity either. This seems to be part of the scientific 'instrumentalist' view of nature, which is incredibly useful but very superficial. |
| 16708 | Newton's forces were accused of being the scholastics' real qualities [Pasnau on Newton] |
| Full Idea: Newton's reliance on the notion of force was widely criticised as marking in effect a return to real qualities. | |
| From: comment on Isaac Newton (Principia Mathematica [1687]) by Robert Pasnau - Metaphysical Themes 1274-1671 19.7 | |
| A reaction: The objection is to forces that are separate from the bodies they act on. This is one of the reasons why modern metaphysics needs the concept of an intrinsic disposition or power, placing the forces in the stuff. |
| 13153 | I am studying the quantities and mathematics of forces, not their species or qualities [Newton] |
| Full Idea: I consider in this treatise not the species of forces and their physical qualities, but their quantities and mathematical proportions. | |
| From: Isaac Newton (Principia Mathematica [1687], 1.1.11 Sch) | |
| A reaction: Note that Newton is not denying that one might contemplate the species and qualities of forces, as I think Leibniz tried to do, thought he didn't cast any detailed light on them. It is the gap between science and metaphysics. |
| 12724 | The aim is to discover forces from motions, and use forces to demonstrate other phenomena [Newton] |
| Full Idea: The basic problem of philosophy seems to be to discover the forces of nature from the phenomena of motions and then to demonstrate the other phenomena from these forces. | |
| From: Isaac Newton (Principia Mathematica [1687], Pref 1st ed), quoted by Daniel Garber - Leibniz:Body,Substance,Monad 4 | |
| A reaction: This fits in with the description-of-regularity approach to laws which Newton had acquired from Galileo, rather than the essentialist attitude to forces of Leibniz, though Newton has smatterings of essentialism. |
| 13593 | Newton showed that falling to earth and orbiting the sun are essentially the same [Newton, by Ellis] |
| Full Idea: Newton showed that the apparently different kinds of processes of falling towards the earth and orbiting the sun are essentially the same. | |
| From: report of Isaac Newton (Principia Mathematica [1687]) by Brian Ellis - Scientific Essentialism 3.08 | |
| A reaction: I quote this to illustrate Newton's permanent achievement in science, in the face of a tendency to say that he was 'outmoded' by the advent of General Relativity. Newton wasn't interestingly wrong. He was very very right. |
| 20969 | Early Newtonians could not formulate conservation of energy, having no concept of potential energy [Newton, by Papineau] |
| Full Idea: A barrier to the formulation of an energy conservation principle by early Newtonians was their lack of a notion of potential energy. | |
| From: report of Isaac Newton (Principia Mathematica [1687]) by David Papineau - Thinking about Consciousness App 3 n5 | |
| A reaction: Interestingly, the notions of potentiality and actuality were central to Aristotle, but Newtonians had just rejected all of that. |
| 17013 | Absolute space is independent, homogeneous and immovable [Newton] |
| Full Idea: Absolute space, of its own nature without reference to anything external, always remains homogeneous and immovable. | |
| From: Isaac Newton (Principia Mathematica [1687], Def 8 Schol) | |
| A reaction: This would have to be a stipulation, rather than an assertion of fact, since whether space is 'immovable' is either incoherent or unknowable. |
| 22915 | Newton needs intervals of time, to define velocity and acceleration [Newton, by Le Poidevin] |
| Full Idea: Both Newton's First and Second Laws of motion make implicit reference to equal intervals of time. For a body is moving with constant velocity if it covers the same distance in a series of equal intervals (and similarly with acceleration). | |
| From: report of Isaac Newton (Principia Mathematica [1687]) by Robin Le Poidevin - Travels in Four Dimensions 01 'Time' | |
| A reaction: [Le Poidevin spells out the acceleration point] You can see why he needs time to be real, if measured chunks of it figure in his laws. |
| 22893 | Newton thought his laws of motion needed absolute time [Newton, by Bardon] |
| Full Idea: Newton's reason for embracing absolute space, time and motion was that he thought that universal laws of motions were describable only in such terms. Because actual motions are irregular, the time of universal laws of motion cannot depend on them. | |
| From: report of Isaac Newton (Principia Mathematica [1687]) by Adrian Bardon - Brief History of the Philosophy of Time 3 'Replacing' | |
| A reaction: I'm not sure of the Einsteinian account of the laws of motion. |
| 17012 | Time exists independently, and flows uniformly [Newton] |
| Full Idea: Absolute, true, and mathematical time, in and of itself and of its own nature, without reference to anything external, flows uniformly and by another name is called duration. | |
| From: Isaac Newton (Principia Mathematica [1687], Def 8 Schol) | |
| A reaction: This invites the notorious question of, if time flows uniformly, how fast time flows. Maybe we should bite the bullet and say 'one second per second', or maybe we should say 'this fact is beyond our powers of comprehension'. |
| 14012 | Absolute time, from its own nature, flows equably, without relation to anything external [Newton] |
| Full Idea: Absolute, true, and mathematical time, of itself, and from its own nature, flows equably, without relation to anything external. | |
| From: Isaac Newton (Principia Mathematica [1687], I:Schol after defs), quoted by Craig Bourne - A Future for Presentism 5.1 | |
| A reaction: I agree totally with this, and I don't care what any modern relativity theorists say. It think Shoemaker's argument gives wonderful support to Newton. |
| 22954 | Newtonian mechanics does not distinguish negative from positive values of time [Newton, by Coveney/Highfield] |
| Full Idea: In Newton's laws of motion time is squared, so a negative value gives the same result as a positive value, which means Newtonian mechanics cannot distinguish between the two directions of time. | |
| From: report of Isaac Newton (Principia Mathematica [1687]) by P Coveney / R Highfield - The Arrow of Time 2 'anatomy' | |
| A reaction: Maybe Newton just forgot to mention that negative values were excluded. (Or was he unaware of the sequence of negative integers?). Too late now - he's done it. |
| 17015 | If there is no uniform motion, we cannot exactly measure time [Newton] |
| Full Idea: It is possible that there is no uniform motion by which time may have an exact measure. All motions can be accelerated and retarded, but the flow of absolute time cannot be changed. | |
| From: Isaac Newton (Principia Mathematica [1687], Def 8 Schol) |
| 17025 | If a perfect being does not rule the cosmos, it is not God [Newton] |
| Full Idea: A being, however perfect, without dominion is not the Lord God. | |
| From: Isaac Newton (Principia Mathematica [1687], Bk 3 Gen Schol) |
| 4066 | It seems that 'exists' could sometimes be a predicate [Crane] |
| Full Idea: The view that 'exists' is never a predicate is not plausible. | |
| From: Tim Crane (Elements of Mind [2001], 1.7) | |
| A reaction: He doesn't enlarge. Russell says 'exists' is a quantifier. 'Your very existence offends me - I hope it is confiscated'. |
| 17024 | The elegance of the solar system requires a powerful intellect as designer [Newton] |
| Full Idea: This most elegant system of the sun, planets, and comets could not have arisen without the design and dominion of an intelligent and powerful being. | |
| From: Isaac Newton (Principia Mathematica [1687], Bk 3 Gen Schol) |