72 ideas
| 1798 | He studied philosophy by suspending his judgement on everything [Pyrrho, by Diog. Laertius] |
| Full Idea: He studied philosophy on the principle of suspending his judgement on all points. | |
| From: report of Pyrrho (reports [c.325 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 09.Py.3 | |
| A reaction: In what sense was Pyrrho a philosopher, then? He must have asserted SOME generalised judgments. |
| 5486 | Essentialism says metaphysics can't be done by analysing unreliable language [Ellis] |
| Full Idea: The new essentialism leads to a turning away from semantic analysis as a fundamental tool for the pursuit of metaphysical aims, ..since there is no reason to think that the language we speak accurately reflects the kind of world we live in. | |
| From: Brian Ellis (The Philosophy of Nature: new essentialism [2002], Ch.7) | |
| A reaction: The last part of that strikes me as false. We have every reason to think that a lot of our language very accurately reflects reality. It had better, because we have no plan B. We should analyse our best concepts, but not outdated, culture-laden ones. |
| 1800 | Sceptics say reason is only an instrument, because reason can only be attacked with reason [Pyrrho, by Diog. Laertius] |
| Full Idea: The Sceptics say that they only employ reason as an instrument, because it is impossible to overturn the authority of reason, without employing reason. | |
| From: report of Pyrrho (reports [c.325 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 09.Py.8 |
| 5468 | Properties are 'dispositional', or 'categorical' (the latter as 'block' or 'intrinsic' structures) [Ellis, by PG] |
| Full Idea: 'Dispositional' properties involve behaviour, and 'categorical properties' are structures in two or more dimensions. 'Block' structures (e.g. molecules) depend on other things, and 'instrinsic' structures (e.g. fields) involve no separate parts. | |
| From: report of Brian Ellis (The Philosophy of Nature: new essentialism [2002], Ch.4) by PG - Db (ideas) | |
| A reaction: This is an essentialist approach to properties, and sounds correct to me. The crucial preliminary step to understanding properties is to eliminate secondary qualities (e.g. colour), which are not properties at all, and cause confusion. |
| 5469 | The passive view of nature says categorical properties are basic, but others say dispositions [Ellis] |
| Full Idea: 'Categorical realism' is the most widely accepted theory of dispositional properties, because passivists can accept it, ..that is, that dispositions supervene on categorical properties; ..the opposite would imply nature is active and reactive. | |
| From: Brian Ellis (The Philosophy of Nature: new essentialism [2002], Ch.4) | |
| A reaction: Essentialists believe 'the opposite' - i.e. that dispositions are fundamental, and hence that the essence of nature is active. See 5468 for explanations of the distinctions. I am with the essentialists on this one. |
| 5456 | Redness is not a property as it is not mind-independent [Ellis] |
| Full Idea: Redness is not a property, because it has no mind-independent existence. | |
| From: Brian Ellis (The Philosophy of Nature: new essentialism [2002], Ch.3) | |
| A reaction: Well said. Secondary qualities are routinely cited in discussions of properties, and they shouldn't be. Redness causes nothing to happen in the physical world, unless a consciousness experiences it. |
| 5481 | Properties have powers; they aren't just ways for logicians to classify objects [Ellis] |
| Full Idea: One cannot think of a property as just a set of objects in a domain (as Fregean logicians do), as though the property has no powers, but is just a way of classifying objects. | |
| From: Brian Ellis (The Philosophy of Nature: new essentialism [2002], Ch.7) | |
| A reaction: I agree. It is sometimes suggested that properties are what 'individuate' objects, but how could they do that if they didn't have some power? If properties are known by their causal role, why do they have that causal role? |
| 5458 | Nearly all fundamental properties of physics are dispositional [Ellis] |
| Full Idea: With few, if any, exceptions, the fundamental properties of physical theory are dispositional properties of the things that have them. | |
| From: Brian Ellis (The Philosophy of Nature: new essentialism [2002], Ch.3) | |
| A reaction: He is denying that they are passive (as Locke saw primary qualities), and says they are actively causal, or else capacities or propensities. Sounds right to me. |
| 5443 | Kripke and others have made essentialism once again respectable [Ellis] |
| Full Idea: The revival of essentialism owes much to the work of Saul Kripke and Hilary Putnam, who made belief in essences once again respectable, with Harré and Madden arguing that there were real causal powers in nature. | |
| From: Brian Ellis (The Philosophy of Nature: new essentialism [2002], Intro) | |
| A reaction: It seems to me important to separate two stages of this: 1) causation results from essences, and 2) essences can never change. The first seems persuasive to me. For the second, see METAPHYSICS/IDENTITY/COUNTERPARTS. |
| 5444 | 'Individual essences' fix a particular individual, and 'kind essences' fix the kind it belongs to [Ellis] |
| Full Idea: The new essentialism retains Aristotelian ideas about essential properties, but it distinguishes more clearly between 'individual essences' and 'kind essences'; the former define a particular individual, the latter what kind it belongs to. | |
| From: Brian Ellis (The Philosophy of Nature: new essentialism [2002], Ch.1) | |
| A reaction: This might actually come into conflict with Aristotle, who seems to think that my personal essence is largely a human nature I share with everyone else. The new distinction is trying to keep the Kantian individual on the stage. |
| 5462 | Essential properties are usually quantitatively determinate [Ellis] |
| Full Idea: Most of the essential properties of things are quantitatively determinate properties. | |
| From: Brian Ellis (The Philosophy of Nature: new essentialism [2002], Ch.3) | |
| A reaction: This makes the essential nature of the world very much the province of science, which deals in quantities and equations. Essentialists must deal with mental events, as well as basic physics. |
| 5448 | 'Real essence' makes it what it is; 'nominal essence' makes us categorise it a certain way [Ellis] |
| Full Idea: The 'real essence' of a thing is that set of its properties or structures in virtue of which it is a thing of that kind; its 'nominal essence' is the properties or structures in virtue of which it is described as a thing of that kind. | |
| From: Brian Ellis (The Philosophy of Nature: new essentialism [2002], Ch.1) | |
| A reaction: I like this distinction, because it is the kind made by realists like me who are fighting to make philosophers keep their epistemology and their ontology separate. |
| 5477 | One thing can look like something else, without being the something else [Ellis] |
| Full Idea: In considering questions of real possibility, it is important to keep the distinction between what a thing is and what it looks like clearly in mind. There is a possible world containing a horse that could then look like a cow, but it wouldn't BE a horse. | |
| From: Brian Ellis (The Philosophy of Nature: new essentialism [2002], Ch.6) | |
| A reaction: This is an interesting test assertion of the notion that there are essences (although Ellis does not allow that animals actually have essences - how could you, given evolution?). His point is a good one. |
| 5479 | Scientific essentialists say science should define the limits of the possible [Ellis] |
| Full Idea: Scientific essentialists hold that one of the primary aims of science is to define the limits of the possible. | |
| From: Brian Ellis (The Philosophy of Nature: new essentialism [2002], Ch.6) | |
| A reaction: I'm not sure working scientists will go along with that, but I like the claim that philosophy is very much part of the same enterprise as practical science (and NOT subservient to it!). I think of metaphysics as very high level physics. |
| 5483 | Essentialists deny possible worlds, and say possibilities are what is compatible with the actual world [Ellis] |
| Full Idea: Essentialists are modal realists; ..what is really possible, they say, is what is compatible with the natures of things in this world (and this does not commit them to the existence of any world other than the actual world). | |
| From: Brian Ellis (The Philosophy of Nature: new essentialism [2002], Ch.7) | |
| A reaction: This introduces something like 'compatibilities' into our ontology. That must rest on some kind of idea of a 'natural contradiction'. We can discuss the possibilities resulting from essences, but what are the possible variations in the essences? |
| 5447 | Metaphysical necessities are true in virtue of the essences of things [Ellis] |
| Full Idea: Metaphysical necessities are propositions that are true in virtue of the essences of things. | |
| From: Brian Ellis (The Philosophy of Nature: new essentialism [2002], Ch.1) | |
| A reaction: I am cautious about this. It sounds like huge Leibnizian metaphysical claims riding in on the back of a rather sensible new view of the laws of science. How can we justify equating natural necessity with metaphysical necessity? |
| 5476 | Essentialists say natural laws are in a new category: necessary a posteriori [Ellis] |
| Full Idea: Essentialists do not accept the standard position, which says necessity is a priori, and contingency is a posteriori. They have a radically new category: the necessary a posteriori. The laws of nature are, for example, both necessary and a posteriori. | |
| From: Brian Ellis (The Philosophy of Nature: new essentialism [2002], Ch.6) | |
| A reaction: Based on Kripke. I'm cautious about this. Presumably God, who would know the essences, could therefore infer the laws a priori. The laws may follow of necessity from the essences, but the essences can't be known a posteriori to be necessary. |
| 5478 | Imagination tests what is possible for all we know, not true possibility [Ellis] |
| Full Idea: The imaginability test of possibility confuses what is really or metaphysically possible with what is only epistemically possible. ..The latter is just what is possible for all we know. | |
| From: Brian Ellis (The Philosophy of Nature: new essentialism [2002], Ch.6) |
| 5482 | Possible worlds realism is only needed to give truth conditions for modals and conditionals [Ellis] |
| Full Idea: The main trouble with possible worlds realism is that the only reason anyone has, or ever could have, to believe in other possible worlds (other than this one) is that they are needed, apparently, to provide truth conditions for modals and conditionals. | |
| From: Brian Ellis (The Philosophy of Nature: new essentialism [2002], Ch.7) | |
| A reaction: This attacks Lewis. Ellis makes this sound like a trivial technicality, but if our metaphysics is going to make sense it must cover modals and conditionals. What do they actually mean? Lewis has a theory, at least. |
| 5453 | Essentialists mostly accept the primary/secondary qualities distinction [Ellis] |
| Full Idea: Essentialists mostly accept the distinction between primary and secondary qualities, ..where the primary qualities of things are those that are intrinsic to the objects that have them. | |
| From: Brian Ellis (The Philosophy of Nature: new essentialism [2002], Ch.3) | |
| A reaction: One reason I favour essentialism is because I have always thought that the primary/secondary distinction was a key to understanding the world. 'Primary' gets at the ontology, 'secondary' shows us the epistemology. |
| 5466 | Primary qualities are number, figure, size, texture, motion, configuration, impenetrability and (?) mass [Ellis] |
| Full Idea: For Boyle, Locke and Newton, the qualities inherent in bodies were just the primary qualities, namely number, figure, size, texture, motion and configuration of parts, impenetrability and, perhaps, body (or mass). | |
| From: Brian Ellis (The Philosophy of Nature: new essentialism [2002], Ch.4) | |
| A reaction: It is nice to have a list. Ellis goes on to say these are too passive, and urges dispositions as primary. Even so, the original seventeenth century insight seems to me a brilliant step forward in our understanding of the world. |
| 6595 | If we need a criterion of truth, we need to know whether it is the correct criterion [Pyrrho, by Fogelin] |
| Full Idea: Against the Stoics, the Pyrrhonians argued that if someone presents a criterion of truth, then it will be important to determine whether it is the correct criterion. | |
| From: report of Pyrrho (reports [c.325 BCE]) by Robert Fogelin - Walking the Tightrope of Reason Ch.4 | |
| A reaction: Hence Davidson says that attempts to define truth are 'folly'. If something has to be taken as basic, then truth seems a good candidate (since, for example, logical operators could not otherwise be defined by means of 'truth' tables). |
| 6593 | The Pyrrhonians attacked the dogmas of professors, not ordinary people [Pyrrho, by Fogelin] |
| Full Idea: The attacks of the Pyrrhonian sceptics are directed against the dogmas of the 'professors', not against the beliefs of the common people pursuing the business of daily life. | |
| From: report of Pyrrho (reports [c.325 BCE]) by Robert Fogelin - Walking the Tightrope of Reason Ch.4 | |
| A reaction: This may be because they thought that ordinary people were too confused to be worth attacking, rather than because they lived in a state of beautifully appropriate beliefs. Naïve realism is certainly worth attacking. |
| 6592 | Academics said that Pyrrhonians were guilty of 'negative dogmatism' [Pyrrho, by Fogelin] |
| Full Idea: The ancient Academic sceptics charged the Pyrrhonian sceptics with 'negative dogmatism' when they claimed that a certain kind of knowledge is impossible. | |
| From: report of Pyrrho (reports [c.325 BCE]) by Robert Fogelin - Walking the Tightrope of Reason Ch.4 | |
| A reaction: It is this kind of point which should push us towards some sort of rationalism, because certain a priori 'dogmas' seem to be indispensable to get any sort of discussion off the ground. The only safe person is Cratylus (see Idea 578). |
| 1805 | Judgements vary according to local culture and law (Mode 5) [Pyrrho, by Diog. Laertius] |
| Full Idea: Fifth mode: judgements vary according to local custom, law and culture (Persians marry their daughters). | |
| From: report of Pyrrho (reports [c.325 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 09.Py.9 |
| 1803 | Objects vary according to which sense perceives them (Mode 3) [Pyrrho, by Diog. Laertius] |
| Full Idea: Third mode: things like an apple vary according to which sense perceives them (yellow, sweet, and fragrant). | |
| From: report of Pyrrho (reports [c.325 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 09.Py.9 |
| 1801 | Animals vary in their feelings and judgements (Mode 1) [Pyrrho, by Diog. Laertius] |
| Full Idea: First mode: animals vary in their feelings and judgements (of food, for example). | |
| From: report of Pyrrho (reports [c.325 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 09.Py.9 |
| 1804 | Perception varies with madness or disease (Mode 4) [Pyrrho, by Diog. Laertius] |
| Full Idea: Fourth mode: perceivers vary in their mental and physical state (such as the mad and the sick). | |
| From: report of Pyrrho (reports [c.325 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 09.Py.9 |
| 1808 | Perception of things depends on their size or quantity (Mode 8) [Pyrrho, by Diog. Laertius] |
| Full Idea: Eighth mode: perceptions of things depend on their magnitude or quantity (food and wine). | |
| From: report of Pyrrho (reports [c.325 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 09.Py.9 |
| 1806 | Perception of objects depends on surrounding conditions (Mode 6) [Pyrrho, by Diog. Laertius] |
| Full Idea: Sixth mode: the perception of an object depends on surrounding conditions (sunlight and lamplight). | |
| From: report of Pyrrho (reports [c.325 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 09.Py.9 |
| 1809 | Perception is affected by expectations (Mode 9) [Pyrrho, by Diog. Laertius] |
| Full Idea: Ninth mode: we perceive things according to what we expect (earthquakes and sunshine). | |
| From: report of Pyrrho (reports [c.325 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 09.Py.9 |
| 1807 | Perception varies with viewing distance and angle (Mode 7) [Pyrrho, by Diog. Laertius] |
| Full Idea: Seventh mode: perception varies according to viewing distance and angle (the sun, and a dove's neck). | |
| From: report of Pyrrho (reports [c.325 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 09.Py.9 |
| 1810 | Perception and judgement depend on comparison (Mode 10) [Pyrrho, by Diog. Laertius] |
| Full Idea: Tenth mode: perceptions and judgements depend on comparison (light/heavy, above/below). | |
| From: report of Pyrrho (reports [c.325 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 09.Py.9 |
| 1802 | Individuals vary in responses and feelings (Mode 2) [Pyrrho, by Diog. Laertius] |
| Full Idea: Second mode: individual men vary in responses and feelings (heat and cold, for example). | |
| From: report of Pyrrho (reports [c.325 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 09.Py.9 |
| 5485 | Emeralds are naturally green, and only an external force could turn them blue [Ellis] |
| Full Idea: Emeralds cannot all turn blue in 2050 (as Nelson Goodman envisaged), because to do so they would have to have an extrinsically variable nature. | |
| From: Brian Ellis (The Philosophy of Nature: new essentialism [2002], Ch.7) | |
| A reaction: I was never very impressed by the 'grue' problem, probably for this reason, but also because Goodman probably thought predicates and properties are the same thing, which they aren't (Idea 5457). |
| 5484 | Essentialists don't infer from some to all, but from essences to necessary behaviour [Ellis] |
| Full Idea: For essentialists the problem of induction reduces to discovering what natural kinds there are, and identifying their essential problems and structures. We then know how they must behave in any world, and there is no inference from some to all. | |
| From: Brian Ellis (The Philosophy of Nature: new essentialism [2002], Ch.7) | |
| A reaction: The obvious question is how you would determine the essences if you are not allowed to infer 'from some to all'. Personally I don't see induction as a problem, because it is self-evidently rational in a stable world. Hume was right to recommend caution. |
| 5457 | Predicates assert properties, values, denials, relations, conventions, existence and fabrications [Ellis, by PG] |
| Full Idea: As well as properties, predicates can assert evaluation, denial, relations, conventions, existence or fabrication. | |
| From: report of Brian Ellis (The Philosophy of Nature: new essentialism [2002], Ch.3) by PG - Db (ideas) | |
| A reaction: This seems important, in order to disentangle our ontological commitments from our language, which was a confusion that ran throughout twentieth-century philosophy. A property is a real thing in the world, not a linguistic convention. |
| 5488 | Regularity theories of causation cannot give an account of human agency [Ellis] |
| Full Idea: A Humean theory of causation (as observed regularities) makes it very difficult for anyone even to suggest a plausible theory of human agency. | |
| From: Brian Ellis (The Philosophy of Nature: new essentialism [2002], Ch.7) | |
| A reaction: I'm not quite sure what a 'theory' of human agency would look like. Hume himself said we only get to understand our mental powers from repeated experience (Idea 2220). How do we learn about the essence of our own will? |
| 5489 | Humans have variable dispositions, and also power to change their dispositions [Ellis] |
| Full Idea: It seems that human beings not only have variable dispositional properties, as most complex systems have, but also meta-powers: powers to change their own dispositional properties. | |
| From: Brian Ellis (The Philosophy of Nature: new essentialism [2002], Ch.7) | |
| A reaction: This seems to me a key to how we act, and also to morality. 'What dispositions do you want to have?' is the central question of virtue theory. Humans are essentially multi-level thinkers. Irony is the window into the soul. |
| 5490 | Essentialism fits in with Darwinism, but not with extreme politics of left or right [Ellis] |
| Full Idea: The extremes of left and right in politics have much more reason than Darwinists to be threatened by the 'new essentialism', because it must reinstate the concept of human nature. | |
| From: Brian Ellis (The Philosophy of Nature: new essentialism [2002], Ch.7) | |
| A reaction: The point being that political extremes go against the grain of our nature. Personally I am favour of essentialism, and human nature. I notice that Steven Pinker is now defending human nature, from a background of linguistics and psychology. |
| 5472 | Natural kinds are of objects/substances, or events/processes, or intrinsic natures [Ellis] |
| Full Idea: Natural kinds appear to be of objects or substances, or of events or processes, or of the intrinsic nature of things; hence there should be laws of nature specific to each of these categories. | |
| From: Brian Ellis (The Philosophy of Nature: new essentialism [2002], Ch.5) | |
| A reaction: It is nice to see someone actually discussing what sort of natural kinds there are, instead of getting bogged down in how natural kinds terms get their meaning or reference. Ellis recognises that 'intrinsic nature' needs some discussion. |
| 5471 | Essentialism says natural kinds are fundamental to nature, and determine the laws [Ellis] |
| Full Idea: According to essentialists, the world is wholly structured at the most fundamental level into natural kinds, and the laws of nature are all determined by those kinds. | |
| From: Brian Ellis (The Philosophy of Nature: new essentialism [2002], Ch.5) | |
| A reaction: I am a fan of this view, despite being cautious about claims that natural kinds have necessary identity. Why are the essences active? That is the old Greek puzzle about the origin of movement. And why are natural kinds stable? |
| 5446 | For essentialists two members of a natural kind must be identical [Ellis] |
| Full Idea: Modern essentialists would insist that any two members of the same natural kind must be identical in all essential respects. | |
| From: Brian Ellis (The Philosophy of Nature: new essentialism [2002], Ch.1) | |
| A reaction: For this reason, animals no longer qualify as natural kinds, but electrons, gold atoms, and water molecules do. My sticking point is when anyone asserts that an electron necessarily has (say) its mass. Why no close counterpart of electrons? |
| 5480 | The whole of our world is a natural kind, so all worlds like it necessarily have the same laws [Ellis] |
| Full Idea: It is plausible to suppose that the world is an instance of a natural kind, ..and what is naturally necessary in our world is what must be true in any world of the same natural kind. | |
| From: Brian Ellis (The Philosophy of Nature: new essentialism [2002], Ch.6) | |
| A reaction: This is putting an awful lot of metaphysical weight on the concept of a 'natural kind', so it had better be a secure one. If we accept that natural laws necessarily follow from essences, why shouldn't the whole of our world have an essence, as water does? |
| 3062 | There are no causes, because they are relative, and alike things can't cause one another [Pyrrho, by Diog. Laertius] |
| Full Idea: The idea of cause is relative to that of which it is the cause, and so has no real existence. …Also cause must either be body causing body, or incorporeal causing incorporeal, and neither of these is possible. | |
| From: report of Pyrrho (reports [c.325 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 09.11.11 |
| 5445 | Essentialists regard inanimate objects as genuine causal agents [Ellis] |
| Full Idea: Essentialist suppose that the inanimate objects of nature are genuine causal agents: things capable of acting or interacting. | |
| From: Brian Ellis (The Philosophy of Nature: new essentialism [2002], Intro) | |
| A reaction: I have no idea how one might demonstrate such a fact, even though it seems to stare us in the face. This is where science bumps into philosophy. I find myself intuitively taking the essentialist side quite strongly. |
| 5463 | Essentialists believe causation is necessary, resulting from dispositions and circumstances [Ellis] |
| Full Idea: Essentialists believe elementary causal relations involve necessary connections between events, namely between the displays of dispositional properties and the circumstances that give rise to them. | |
| From: Brian Ellis (The Philosophy of Nature: new essentialism [2002], Ch.4) | |
| A reaction: I like essentialism, but I feel a Humean caution about talk of 'natural necessity'. Let's just say that causation seems to be entirely the result of the nature of how things are. How things could be is a large topic for little mites like us. |
| 5491 | A general theory of causation is only possible in an area if natural kinds are involved [Ellis] |
| Full Idea: A general theory of causation in an area is possible only if the kinds of entities under investigation can reasonably be assumed to belong to natural kinds. | |
| From: Brian Ellis (The Philosophy of Nature: new essentialism [2002], Ch.7) | |
| A reaction: Human beings will be a problem, and also different levels of natural kinds (e.g. a chemical and an organism). 'Natural kind' is a very loose concept. He is referring to scientific, rather than philosophical, theories, I presume. |
| 5442 | For 'passivists' behaviour is imposed on things from outside [Ellis] |
| Full Idea: A 'passivist' believes that the tendencies of things to behave as they do can never be inherent in the things themselves; they must always be imposed on them from the outside. | |
| From: Brian Ellis (The Philosophy of Nature: new essentialism [2002], Intro) | |
| A reaction: This is the medieval view, inherited by Newton and Hume, which makes miracles a possibility, and makes the laws of nature contingent. Essentialism disagree. I think I am with the essentialists. |
| 5473 | The laws of nature imitate the hierarchy of natural kinds [Ellis] |
| Full Idea: If the natural kinds are divided into hierarchical categories, then essentialists would expect the laws of nature also to divide up into these categories, with the same hierarchy. | |
| From: Brian Ellis (The Philosophy of Nature: new essentialism [2002], Ch.5) | |
| A reaction: This seems to me a real step forwards in our understanding of nature, and hence a nice example of the contribution which philosophy can make, instead of just physics. |
| 5474 | Laws of nature tend to describe ideal things, or ideal circumstances [Ellis] |
| Full Idea: Most of the propositions we think of as being (or as expressing) genuine laws of nature seem to describe only the behaviour of ideal kinds of things, or of things in ideal circumstances. | |
| From: Brian Ellis (The Philosophy of Nature: new essentialism [2002], Ch.5) | |
| A reaction: Ellis this suggests that this phenomenon is because science aims at broad understanding instead of strict prediction. Do we simplify because we are a bit dim? Or is it because generalisation wouldn't exist without idealisation and abstraction? |
| 5475 | We must explain the necessity, idealisation, ontology and structure of natural laws [Ellis] |
| Full Idea: There are four major problems about the laws of nature: a necessity problem (must they be true?), an idealisation problem (why is this preferable?), an ontological problem (their grounds), and a structural problem (their relationships). | |
| From: Brian Ellis (The Philosophy of Nature: new essentialism [2002], Ch.5) | |
| A reaction: One might also ask why the laws (or their underlying essences) are the way they are, and not some other way, though the prospects of answering that don't look good. I don't think we should be satisfied with saying all of these questions are hopeless. |
| 5460 | Causal relations cannot be reduced to regularities, as they could occur just once [Ellis] |
| Full Idea: Causal relations cannot be reduced to mere regularities, as Hume supposed, as they could exist as a singular case, even if it never happened on more than one occasions. | |
| From: Brian Ellis (The Philosophy of Nature: new essentialism [2002], Ch.3) | |
| A reaction: This seems to be the key reason for modern views moving away from Hume. The suspicion is that regularity is a test for or symptom of causation, but we are deeply committed to the real nature of causation being whatever creates the regularities. |
| 5459 | Essentialists say dispositions are basic, rather than supervenient on matter and natural laws [Ellis] |
| Full Idea: Essentialists say that dispositional properties may be fundamental, whereas for a passivist such qualities are not primary, but supervene on the primary qualities of matter, and on the laws of nature. | |
| From: Brian Ellis (The Philosophy of Nature: new essentialism [2002], Ch.3) | |
| A reaction: I am strongly in favour of this view of nature. Without essentialism, we have laws of nature arising out of a total void (or God), and arbitrarily imposing themselves on matter. What are the 'primary qualities of matter', if not dispositions? |
| 5461 | The essence of uranium is its atomic number and its electron shell [Ellis] |
| Full Idea: The essential properties of uranium are its atomic number, and the common electron shell structure for all uranium atoms. | |
| From: Brian Ellis (The Philosophy of Nature: new essentialism [2002], Ch.3) | |
| A reaction: For those who deny essences (e.g. Quineans) this is a nice challenge. You might have to add accounts of the essences of the various particles that make up the atoms. There is nothing arbitrary or conventional about what makes something uranium. |
| 5464 | For essentialists, laws of nature are metaphysically necessary, being based on essences of natural kinds [Ellis] |
| Full Idea: Essentialist believe the laws of nature are metaphysically necessary, because anything that belongs to a natural kind is logically required (or is necessarily disposed) to behave as its essential properties dictate. | |
| From: Brian Ellis (The Philosophy of Nature: new essentialism [2002], Ch.4) | |
| A reaction: What a thrillingly large claim. Best approached with caution.. If we say 'essences make laws, and essences are necessary', we might wonder whether a natural kind essence could be SLIGHTLY different (a counterpart) in another world. |
| 5487 | Essentialism requires a clear separation of semantics, epistemology and ontology [Ellis] |
| Full Idea: Scientific essentialism requires that philosophers distinguish clearly between semantic issues, epistemological issues, and ontological issues. | |
| From: Brian Ellis (The Philosophy of Nature: new essentialism [2002], Ch.7) | |
| A reaction: Music to my ears - but then I think everyone should require that of philosophers, because it where they get themselves most confused. The trouble is that ontology is only obtainable epistemologically, and only expressible semantically. |
| 3063 | Motion can't move where it is, and can't move where it isn't, so it can't exist [Pyrrho, by Diog. Laertius] |
| Full Idea: Motion is not moved in the place in which it is is, and it is impossible that it should be moved in the place in which it is not, so there is no such thing as motion. | |
| From: report of Pyrrho (reports [c.325 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 09.11.11 |
| 21202 | The strong force has a considerably greater range than the weak force [Martin,BR] |
| Full Idea: The strong nuclear force has a range of 10^-15 m, considerably larger than the range of the weak force. | |
| From: Brian R. Martin (Particle Physics [2011], 01) | |
| A reaction: This is because the bosons transmitting the weak force (W+, W-, W°) are much heavier than the gluons of the strong force. |
| 21211 | If an expected reaction does not occur, that implies a conservation law [Martin,BR] |
| Full Idea: If some reaction is not observed when there is apparently nothing to prevent it occurring, it is an indication that a conservation law is in operation. | |
| From: Brian R. Martin (Particle Physics [2011], 07) |
| 21209 | Electron emit and reabsorb photons, which create and reabsorb virtual electrons and positrons [Martin,BR] |
| Full Idea: In QED an electron constantly emits and reabsorbs virtual photons and these photons constantly create and reabsorb pairs of virtual electrons and positrons, and so on. | |
| From: Brian R. Martin (Particle Physics [2011], 06) | |
| A reaction: 'And so on'! These virtual particles have energy, and hence mass. |
| 21201 | A 'field' is just a region to which points can be assigned in space and time [Martin,BR] |
| Full Idea: The word 'field' is simply a shorthand way of saying that a physical property is assigned to the points of space and time in a region. | |
| From: Brian R. Martin (Particle Physics [2011], 01) | |
| A reaction: This is disappointing because I had begun to think that fields were foundational for modern ontology. Turns out they are operational abstractions (according to Martin). Note that a field extends over time. |
| 21212 | The Higgs field, unlike others, has a nozero value in a state without particles [Martin,BR] |
| Full Idea: The Higgs field has the property of having a nonzero value in a state without particles, the vacuum state. Other fields are assumed to have a value zero in a vacuum state. | |
| From: Brian R. Martin (Particle Physics [2011], 09) | |
| A reaction: This seems to make a big difference to our concept of a field, since it has a measurable reality even when there are no particles. So it isn't just a geometrical frame for locating particles. |
| 21205 | Many physicists believe particles have further structure, if only we could see it [Martin,BR] |
| Full Idea: Although standard particles are assumed to be structureless, many physicists believe that if distances could be probed down to 10^-35 m structures would be discovered. | |
| From: Brian R. Martin (Particle Physics [2011], 01) | |
| A reaction: Such probing is said to be probably impossible. And does the division then come to a halt? Aristotle's meditations on this are not irrelevant. |
| 21203 | Uncertainty allows very brief violations of energy conservation - even shorter with higher energies [Martin,BR] |
| Full Idea: The uncertainty principle states that energy conservation can be violated, but only for a limited period of time. As the energy violation increases, the time period within which 'borrowed' energy has to be 'paid back' decreases. | |
| From: Brian R. Martin (Particle Physics [2011], 01) | |
| A reaction: This is the only reason modern physicists ever seem to mention the uncertainty principle. You can ask why this debt must be paid, but it seems to be hidden where the laws of physics may not even apply. |
| 21207 | The Exclusion Principle says no two fermions occupy the same state, with the same numbers [Martin,BR] |
| Full Idea: The 'exclusion principle' initially stated that no two electrons in a system could simultaneously occupy the same quantum state and thus have the same set of quantum numbers. The principle actually applies to all fermions, but not to bosons. | |
| From: Brian R. Martin (Particle Physics [2011], 02) | |
| A reaction: This principle is said to be at the root of atomic structure, making each element unique. What exactly is a 'system'? Why does this principle hold? How do you ensure two women don't wear the same dress at a party? |
| 21204 | The standard model combines theories of strong interaction, and electromagnetic and weak interaction [Martin,BR] |
| Full Idea: As presently formulated, the standard model is two theories. One operates in the sector of strong interaction, and the other in the sector of the electromagnetic and weak interactions. | |
| From: Brian R. Martin (Particle Physics [2011], 01) | |
| A reaction: The first is Quantum Chomodynamics (QCD). The second is Quantum Electrodynamics (QED). Interesting that the weak interaction is included in the latter, which (I take it) means there is an electro-weak union. Interactions are the heart of the model. |
| 21208 | Eletrons don't literally 'spin', because they are point-like [Martin,BR] |
| Full Idea: The picture of a particle spinning like a top is sometime useful, but it is not consistent with the idea of the electron being point-like. In fact there is no analogy for spin in non-quantum physics. | |
| From: Brian R. Martin (Particle Physics [2011], 02) | |
| A reaction: If we take this stuff literally then it blow traditional metaphysics to bits, because an electron has properties without being a substance. In what sense can an electron 'have' properties if it is a point? In interactions they cease to be points. Eh? |
| 21210 | Virtual particles surround any charged particle [Martin,BR] |
| Full Idea: A cloud of virtual particles always surrounds a charged particle. | |
| From: Brian R. Martin (Particle Physics [2011], 06) | |
| A reaction: Here's a nice fact for aspiring Buddhists to meditate on. |
| 21206 | The properties of a particle are determined by its quantum numbers and its mass [Martin,BR] |
| Full Idea: In quantum theory, the full set of quantum numbers defines the state of the particle and, along with its mass, determines its properties. | |
| From: Brian R. Martin (Particle Physics [2011], 02) |
| 21213 | String theory only has one free parameter (tension) - unlike the standard model with 19 [Martin,BR] |
| Full Idea: Unlike the standard model, with its 19 free parameters (including the masses of quarks, coupling constants and mixing angles), string theories have a single free paramater: the string tension. | |
| From: Brian R. Martin (Particle Physics [2011], 10) | |
| A reaction: This must be one feature in favour of string theory, despite its problems. |
| 21200 | An 'element' is what cannot be decomposed by chemistry [Martin,BR] |
| Full Idea: In the modern sense 'element' means a substance that cannot be decomposed by the methods of chemistry. | |
| From: Brian R. Martin (Particle Physics [2011], 01) |