67 ideas
| 16123 | Whenever you perceive a community of things, you should also hunt out differences in the group [Plato] |
| Full Idea: The rule is that when one perceives first the community between the members of a group of many things, one should not desist until one sees in it all those differences that are located in classes. | |
| From: Plato (The Statesman [c.356 BCE], 285b) | |
| A reaction: He goes on to recommend the opposite as well - see community even when there appears to be nothing but differences. I take this to be analysis, just as much as modern linguistic approaches are. Analyse the world, not language. |
| 2463 | A standard naturalist view is realist, externalist, and computationalist, and believes in rationality [Fodor] |
| Full Idea: There seems to be an emerging naturalist consensus that is Realist in ontology and epistemology, externalist in semantics, and computationalist in cognitive psychology, which nicely allows us to retain our understanding of ourselves as rational creatures. | |
| From: Jerry A. Fodor (The Elm and the Expert [1993], §4) |
| 16125 | To reveal a nature, divide down, and strip away what it has in common with other things [Plato] |
| Full Idea: Let's take the kind posited and cut it in two, .then follow the righthand part of what we've cut, and hold onto things that the sophist is associated with until we strip away everything he has in common with other things, then display his peculiar nature. | |
| From: Plato (The Statesman [c.356 BCE], 264e) | |
| A reaction: This seems to be close to Aristotle's account of definition, when he is trying to get at what-it-is-to-be some thing. But if you strip away everything the definiendum has in common with other things, will anything remain? |
| 16124 | No one wants to define 'weaving' just for the sake of weaving [Plato] |
| Full Idea: I don't suppose that anyone with any sense would want to hunt down the definition of 'weaving' for the sake of weaving itself. | |
| From: Plato (The Statesman [c.356 BCE], 285d) | |
| A reaction: The point seems to be that the definition brings out the connections between weaving and other activities and objects, thus enlarging our understanding. |
| 2435 | Psychology has to include the idea that mental processes are typically truth-preserving [Fodor] |
| Full Idea: A psychology that can't make sense of such facts as that mental processes are typically truth-preserving is ipso facto dead in the water. | |
| From: Jerry A. Fodor (The Elm and the Expert [1993], §1.3) |
| 2442 | Inferences are surely part of the causal structure of the world [Fodor] |
| Full Idea: Inferences are surely part of the causal structure of the world. | |
| From: Jerry A. Fodor (The Elm and the Expert [1993], §3) |
| 5961 | The soul gets its goodness from god, and its evil from previous existence. [Plato] |
| Full Idea: From its composer the soul possesses all beautiful things, but from its former condition, everything that proves to be harsh and unjust in heaven. | |
| From: Plato (The Statesman [c.356 BCE], 273b) | |
| A reaction: A neat move to explain the origins of evil (or rather, to shift the problem of evil to a long long way from here). This view presumably traces back to the views of Empedocles on good and evil. Can the soul acquire evil in its current existence? |
| 2462 | Control of belief is possible if you know truth conditions and what causes beliefs [Fodor] |
| Full Idea: Premeditated cognitive management is possible if knowing the contents of one's thoughts would tell you what would make them true and what would cause you to have them. | |
| From: Jerry A. Fodor (The Elm and the Expert [1993], §4) | |
| A reaction: I love the idea of 'cognitive management'. Since belief is fairly involuntary, I subject myself to the newspapers, books, TV and conversation which will create the style of beliefs to which I aspire. Why? |
| 2460 | Participation in an experiment requires agreement about what the outcome will mean [Fodor] |
| Full Idea: To be in the audience for an experiment you have to believe what the experimenter believes about what the outcome would mean, but not necessarily what the outcome will be. | |
| From: Jerry A. Fodor (The Elm and the Expert [1993], §4) |
| 2461 | An experiment is a deliberate version of what informal thinking does all the time [Fodor] |
| Full Idea: Experimentation is an occasional and more or less self-conscious exercise in what informal thinking does all the time without thinking about it. | |
| From: Jerry A. Fodor (The Elm and the Expert [1993], §4) |
| 2454 | We can deliberately cause ourselves to have true thoughts - hence the value of experiments [Fodor] |
| Full Idea: A creature that knows what makes its thoughts true and what would cause it to have them, could therefore cause itself to have true thoughts. …This would explain why experimentation is so close to the heart of our cognitive style. | |
| From: Jerry A. Fodor (The Elm and the Expert [1993], §4) |
| 2455 | Interrogation and experiment submit us to having beliefs caused [Fodor] |
| Full Idea: You can put yourself into a situation where you may be caused to believe that P. Putting a question to someone who is in the know is one species of this behaviour, and putting a question to Nature (an experiment) is another. | |
| From: Jerry A. Fodor (The Elm and the Expert [1993], §4) |
| 17405 | If a theory can be fudged, so can observations [Scerri] |
| Full Idea: A theorist may have designed his theory to fit the facts, but is it not equally possible for observers to be influenced by a theory in their report of experimental facts? | |
| From: Eric R. Scerri (The Periodic Table [2007], 05 'Power') | |
| A reaction: This is in reply to Lipton's claim that prediction is better than accommodation because of the 'fudging' problem. The reply is that you might fudge to achieve a prediction. If it was correct, that wouldn't avoid the charge of fudging. |
| 2458 | Theories are links in the causal chain between the environment and our beliefs [Fodor] |
| Full Idea: Theories function as links in the causal chains that run from environmental outcomes to the beliefs that they cause the inquirer to have. | |
| From: Jerry A. Fodor (The Elm and the Expert [1993], §4) |
| 17397 | The periodic system is the big counterexample to Kuhn's theory of revolutionary science [Scerri] |
| Full Idea: The history of the periodic system appears to be the supreme counterexample to Kuhn's thesis, whereby scientific developments proceed in a sudden, revolutionary fashion. | |
| From: Eric R. Scerri (The Periodic Table [2007], 03 'Rapid') | |
| A reaction: What is lovely about the periodic table is that it seems so wonderfully right, and hence no revolution has ever been needed. The big theories of physics and cosmology are much more precarious. |
| 17393 | Scientists eventually seek underlying explanations for every pattern [Scerri] |
| Full Idea: Whenever scientists are presented with a useful pattern or system of classification, it is only a matter of time before the begin to ask whether there may be some underlying explanation for the pattern. | |
| From: Eric R. Scerri (The Periodic Table [2007], Intro 'Evol') | |
| A reaction: Music to my ears, against the idea that the sole aim of science is accurately describe the patterns. |
| 17403 | The periodic table suggests accommodation to facts rates above prediction [Scerri] |
| Full Idea: Rather than proving the value of prediction, the development and acceptance of the periodic table may give us a powerful illustration of the importance of accommodation, that is, the ability of a new scientific theory to explain already known facts. | |
| From: Eric R. Scerri (The Periodic Table [2007], 05 'Intro') | |
| A reaction: The original table made famous predictions, but also just as many wrong ones (Scerri:143), and Scerri thinks this aspect has been overrated. |
| 2443 | I say psychology is intentional, semantics is informational, and thinking is computation [Fodor] |
| Full Idea: I hold that psychological laws are intentional, that semantics is purely informational, and that thinking is computation (and that it is possible to hold all of these assumptions at once). | |
| From: Jerry A. Fodor (The Elm and the Expert [1993], §4) | |
| A reaction: When he puts it baldly like that, it doesn't sound terribly persuasive. Thinking is 'computation'? Raw experience is irrelevant? What is it 'like' to spot an interesting connection between two propositions or concepts? It's not like adding 7 and 5. |
| 2453 | We are probably the only creatures that can think about our own thoughts [Fodor] |
| Full Idea: I think it is likely that we are the only creatures that can think about the contents of our thoughts. | |
| From: Jerry A. Fodor (The Elm and the Expert [1993], §4) | |
| A reaction: I think this is a major idea. If you ask me the traditional question - what is the essential difference between us and other animals? - this is my answer (not language, or reason). We are the metathinkers. |
| 2446 | Cartesians consider interaction to be a miracle [Fodor] |
| Full Idea: The Cartesian view is that the interaction problem does arise, but is unsolvable because interaction is miraculous. | |
| From: Jerry A. Fodor (The Elm and the Expert [1993], §4) | |
| A reaction: A rather unsympathetic statement of the position. Cartesians might think that God could explain to us how interaction works. Cartesians are not mysterians, I think, but they see no sign of any theory of interaction. |
| 2445 | Semantics v syntax is the interaction problem all over again [Fodor] |
| Full Idea: The question how mental representations could be both semantic, like propositions, and causal, like rocks, trees, and neural firings, is arguably just the interaction problem all over again. | |
| From: Jerry A. Fodor (The Elm and the Expert [1993], §4) | |
| A reaction: Interesting way of presenting the problem. If you seem to be confronting the interaction problem, you have probably drifted into a bogus dualist way of thinking. Retreat, and reformulate you questions and conceptual apparatus, till the question vanishes. |
| 2464 | Type physicalism equates mental kinds with physical kinds [Fodor] |
| Full Idea: Type physicalism is, roughly, the doctrine that psychological kinds are identical to neurological kinds. | |
| From: Jerry A. Fodor (The Elm and the Expert [1993], App A n.1) | |
| A reaction: This gets my general support, leaving open the nature of 'kinds'. Presumably the identity is strict, as in 'Hesperus is identical to Phosphorus'. It seems unlikely that if you and I think the 'same' thought, that we have strictly identical brain states. |
| 2447 | Hume has no theory of the co-ordination of the mind [Fodor] |
| Full Idea: What Hume didn't see was that the causal and representational properties of mental symbols have somehow to be coordinated if the coherence of mental life is to be accounted for. | |
| From: Jerry A. Fodor (The Elm and the Expert [1993], §4) | |
| A reaction: Certainly the idea that it all somehow becomes magic at the point where the brain represents the world is incoherent - but it is a bit magical. How can the whole of my garden be in my brain? Weird. |
| 2440 | Propositional attitudes are propositions presented in a certain way [Fodor] |
| Full Idea: Propositional attitudes are really three-place relations, between a creature, a proposition, and a mode of presentation (which are sentences of Mentalese). | |
| From: Jerry A. Fodor (The Elm and the Expert [1993], §2.II) | |
| A reaction: I'm not sure about 'really'! Why do we need a creature? Isn't 'hoping it will rain' a propositional attitude which some creature may or may not have? Fodor wants it to be physical, but it's abstract? |
| 2450 | Rationality has mental properties - autonomy, productivity, experiment [Fodor] |
| Full Idea: Mentalism isn't gratuitous; you need it to explain rationality. Mental causation buys you behaviours that are unlike reflexes in at least three ways: they're autonomous, they're productive, and they're experimental. | |
| From: Jerry A. Fodor (The Elm and the Expert [1993], §4) | |
| A reaction: He makes his three ways sound all-or-nothing, which is (I believe) the single biggest danger when thinking about the mind. "Either you are conscious, or you are not..." |
| 2437 | XYZ (Twin Earth 'water') is an impossibility [Fodor] |
| Full Idea: There isn't any XYZ, and there couldn't be any, and so we don't have to worry about it. | |
| From: Jerry A. Fodor (The Elm and the Expert [1993], §2.I) | |
| A reaction: Jadeite and Nephrite are real enough, which are virtually indistinguishable variants of jade. You just need Twin Jewellers instead of Twin Earths. We could build them, and employ twins to work there. |
| 2441 | Truth conditions require a broad concept of content [Fodor] |
| Full Idea: We need the idea of broad content to make sense of the fact that thoughts have the truth-conditions that they do. | |
| From: Jerry A. Fodor (The Elm and the Expert [1993], §2.II) | |
| A reaction: There seems to be (as Dummett points out) a potential circularity here, as you can hardly know the truth-conditions of something if you don't already know its content. |
| 3114 | Concepts aren't linked to stuff; they are what is caused by stuff [Fodor] |
| Full Idea: If the words of 'Swamp Man' (spontaneously created, with concepts) are about XYZ on Twin Earth, it is not because he's causally connected to the stuff, but because XYZ would cause his 'water' tokens (in the absence of H2O). | |
| From: Jerry A. Fodor (The Elm and the Expert [1993], App B) | |
| A reaction: The sight of the Eiffel tower causes my 'France' tokens, so is my word "France" about the Eiffel Tower? What would cause my 'nothing' tokens? |
| 2452 | Knowing the cause of a thought is almost knowing its content [Fodor] |
| Full Idea: If you know the content of a thought, you know quite a lot about what would cause you to have it. | |
| From: Jerry A. Fodor (The Elm and the Expert [1993], §4) | |
| A reaction: I'm not sure where this fits into the great jigsaw of the mind, but it strikes me as an acute and important observation. The truth of a thought is not essential to make you have it. Ask Othello. |
| 2432 | Is content basically information, fixed externally? [Fodor] |
| Full Idea: I assume intentional content reduces (in some way) to information. …The content of a thought depends on its external relations; on the way that the thought is related to the world, not the way that it is related to other thoughts. | |
| From: Jerry A. Fodor (The Elm and the Expert [1993], §1.2) | |
| A reaction: Does this make Fodor a 'weak' functionalist? The 'strong' version would say a thought is merely a location in a flow diagram, but Fodor's 'mentalism' includes a further 'content' in each diagram box. |
| 2438 | In the information view, concepts are potentials for making distinctions [Fodor] |
| Full Idea: Semantics, according to the informational view, is mostly about counterfactuals; what counts for the identity of my concepts is not what I do distinguish but what I could distinguish if I cared to (even using instruments and experts). | |
| From: Jerry A. Fodor (The Elm and the Expert [1993], §2.I) | |
| A reaction: We all differ in our discriminations (and awareness of expertise), so our concepts would differ, which is bad news for communication (see Idea 223). The view has some plausibility, though. |
| 2439 | Semantic externalism says the concept 'elm' needs no further beliefs or inferences [Fodor] |
| Full Idea: It is the essence of semantic externalism that there is nothing that you have to believe, there are no inferences that you have to accept, to have the concept 'elm'. | |
| From: Jerry A. Fodor (The Elm and the Expert [1993], §2.I) | |
| A reaction: [REMINDER: broad content is filed in 18.C.7, under 'Thought' rather than under language. That is because I am a philospher of thought, rather than of language. |
| 2457 | If meaning is information, that establishes the causal link between the state of the world and our beliefs [Fodor] |
| Full Idea: It is the causal connection between the state of the world and the contents of beliefs that the reduction of meaning to information is designed to insure. | |
| From: Jerry A. Fodor (The Elm and the Expert [1993], §4) | |
| A reaction: I'm not clear why characterising the contents of a belief in terms of its information has to amount to a 'reduction'. A cup of tea isn't reduced to tea. Connections imply duality. |
| 2451 | To know the content of a thought is to know what would make it true [Fodor] |
| Full Idea: If you know the content of a thought, you thereby know what would make the thought true. | |
| From: Jerry A. Fodor (The Elm and the Expert [1993], §4) | |
| A reaction: The truthmaker might by physically impossible, and careful thought might show it to be contradictory - but that wouldn't destroy the meaning. |
| 2433 | For holists no two thoughts are ever quite the same, which destroys faith in meaning [Fodor] |
| Full Idea: If what you are thinking depends on all of what you believe, then nobody ever thinks the same thing twice. …That is why so many semantic holists (Quine, Putnam, Rorty, Churchland, probably Wittgenstein) end up being semantic eliminativists. | |
| From: Jerry A. Fodor (The Elm and the Expert [1993], §1.2b) | |
| A reaction: If linguistic holism is nonsense, this is easily settled. What I say about breakfast is not changed by reading some Gibbon yesterday. |
| 2436 | It is claimed that reference doesn't fix sense (Jocasta), and sense doesn't fix reference (Twin Earth) [Fodor] |
| Full Idea: The standard view is that Frege cases [knowing Jocasta but not mother] show that reference doesn't determine sense, and Twin cases [knowing water but not H2O] show that sense doesn't determine reference. | |
| From: Jerry A. Fodor (The Elm and the Expert [1993], §1.3) | |
| A reaction: How about 'references don't contain much information', and 'descriptions may not fix what they are referring to'? Simple really. |
| 2434 | Broad semantics holds that the basic semantic properties are truth and denotation [Fodor] |
| Full Idea: Broad semantic theories generally hold that the basic semantic properties of thoughts are truth and denotation. | |
| From: Jerry A. Fodor (The Elm and the Expert [1993], §1.2b) | |
| A reaction: I think truth and denotation are the basic semantic properties, but I am dubious about whole-hearted broad semantic theories, so I seem to have gone horribly wrong somewhere. |
| 2459 | Externalist semantics are necessary to connect the contents of beliefs with how the world is [Fodor] |
| Full Idea: You need an externalist semantics to explain why the contents of beliefs should have anything to do with how the world is. | |
| From: Jerry A. Fodor (The Elm and the Expert [1993], §4) | |
| A reaction: Since externalist semantics only emerged in the 1970s, that implies that no previous theory had any notion that language had some connection to how the world is. Eh? |
| 283 | The question of whether or not to persuade comes before the science of persuasion [Plato] |
| Full Idea: The science of whether one must persuade or not must rule over the science capable of persuading. | |
| From: Plato (The Statesman [c.356 BCE], 304c) | |
| A reaction: Plato probably thinks that reason has to be top of the pyramid, but there is always the Nietzschean/romantic question of why we should place such a value on what is rational. |
| 282 | Non-physical beauty can only be shown clearly by speech [Plato] |
| Full Idea: The bodiless things, being the most beautiful and the greatest, are only shown with clarity by speech and nothing else. | |
| From: Plato (The Statesman [c.356 BCE], 286a) | |
| A reaction: Unfortunately this will be true of warped and ugly ideas as well. |
| 281 | The arts produce good and beautiful things by preserving the mean [Plato] |
| Full Idea: It is by preserving the mean that arts produce everything that is good and beautiful. | |
| From: Plato (The Statesman [c.356 BCE], 284b) |
| 22559 | Democracy is the worst of good constitutions, but the best of bad constitutions [Plato, by Aristotle] |
| Full Idea: Plato judged that when the constitution is decent, democracy is the worst of them, but when they are bad it is the best. | |
| From: report of Plato (The Statesman [c.356 BCE], 302e) by Aristotle - Politics 1289b07 | |
| A reaction: Aristotle denies that a good oligarchy is superior. What of technocracy? The challenge is to set up institutions which ensure the health of the democracy. The big modern problem is populists who lie. |
| 17394 | Natural kinds are what are differentiated by nature, and not just by us [Scerri] |
| Full Idea: Natural kinds are realistic scientific entities that are differentiated by nature itself rather than by our human attempts at classification. | |
| From: Eric R. Scerri (The Periodic Table [2007], Intro 'Evol') |
| 17421 | If elements are natural kinds, might the groups of the periodic table also be natural kinds? [Scerri] |
| Full Idea: Elements defined by their atomic numbers are frequently assumed to represent 'natural kinds' in chemistry. ...The question arises as to whether groups of elements appearing in the periodic table might also represent natural kinds. | |
| From: Eric R. Scerri (The Periodic Table [2007], 10 'Elements') | |
| A reaction: Scerri says the distinction is not as sharp as that between the elements. As a realist, he believes there is 'one ideal periodic classification', which would then make the periods into kinds. |
| 17396 | The colour of gold is best explained by relativistic effects due to fast-moving inner-shell electrons [Scerri] |
| Full Idea: Many seemingly mundane properties of elements such as the characteristic color of gold ....can best be explained by relativistic effects due to fast-moving inner-shell electrons. | |
| From: Eric R. Scerri (The Periodic Table [2007], 01 'Under') | |
| A reaction: John Locke - I wish you were reading this! That we could work out the hidden facts of gold, and thereby explain and predict the surface properties we experience, is exactly what Locke thought to be forever impossible. |
| 17420 | The stability of nuclei can be estimated through their binding energy [Scerri] |
| Full Idea: The stability of nuclei can be estimated through their binding energy, a quantity given by the difference between their masses and the masses of their constituent particles. | |
| From: Eric R. Scerri (The Periodic Table [2007], 10 'Stabil') |
| 17411 | If all elements are multiples of one (of hydrogen), that suggests once again that matter is unified [Scerri] |
| Full Idea: The work of Moseley and others rehabilitated Prout's hypothesis that all elements were composites of hydrogen, being exact multiples of 1. ..This revitalized some philososophical notions of the unity of all matter, criticised by Mendeleev and others. | |
| From: Eric R. Scerri (The Periodic Table [2007], 06 'Philos') |
| 17407 | The electron is the main source of chemical properties [Scerri] |
| Full Idea: It is the electron that is mainly responsible for the chemical properties of the elements. | |
| From: Eric R. Scerri (The Periodic Table [2007], 06 'Intro') |
| 17415 | A big chemistry idea is that covalent bonds are shared electrons, not transfer of electrons [Scerri] |
| Full Idea: One of the most influential ideas in modern chemistry is of a covalent bond as a shared pair of electrons (not as transfer of electrons and the formation of ionic bonds). | |
| From: Eric R. Scerri (The Periodic Table [2007], 08 'Intro') | |
| A reaction: Gilbert Newton Lewis was responsible for this. |
| 17392 | How can poisonous elements survive in the nutritious compound they compose? [Scerri] |
| Full Idea: A central mystery of chemistry is how the elements survive in the compounds they form. For example, how can poisonous grey metal sodium combine with green poisonous gas chlorine, to make salt, which is non-poisonous and essential for life? | |
| From: Eric R. Scerri (The Periodic Table [2007], Intro 'Elem') | |
| A reaction: A very nice question which had never occurred to me. If our digestive system pulled the sodium apart from the chlorine, we would die. |
| 17391 | Periodicity and bonding are the two big ideas in chemistry [Scerri] |
| Full Idea: The two big ideas in chemistry are chemical periodicity and chemical bonding, and they are deeply interconnected. | |
| From: Eric R. Scerri (The Periodic Table [2007], Intro 'Per') |
| 17404 | Chemistry does not work from general principles, but by careful induction from large amounts of data [Scerri] |
| Full Idea: Unlike in physics, chemical reasoning does not generally proceed unambiguously from general principles. It is a more inductive science in which large amounts of observational data must be carefully weighed. | |
| From: Eric R. Scerri (The Periodic Table [2007], 05 'Mendel') | |
| A reaction: This is why essentialist thinking was important for Mendeleev, because it kept his focus on the core facts beneath the messy and incomplete data. |
| 17409 | Does radioactivity show that only physics can explain chemistry? [Scerri] |
| Full Idea: Some authors believe that the interpretation of the properties of the elements passed from chemistry to physics as a result of the discovery of radioactivity. ...I believe this view to be overly reductionist. | |
| From: Eric R. Scerri (The Periodic Table [2007], 06 'Radio') | |
| A reaction: It is all a matter of the explanations, and how far down they have to go. If most non-radiocative chemistry doesn't need to mention the physics, then chemistry is largely autonomous. |
| 17418 | It is now thought that all the elements have literally evolved from hydrogen [Scerri] |
| Full Idea: The elements are now believed to have literally evolved from hydrogen by various mechanisms. | |
| From: Eric R. Scerri (The Periodic Table [2007], 10 'Evol) |
| 17398 | 19th C views said elements survived abstractly in compounds, but also as 'material ingredients' [Scerri] |
| Full Idea: In the 19th century abstract elements were believed to be permanent and responsible for observed properties in compounds, but (departing from Aristotle) they were also 'material ingredients', thus linking the metaphysical and material realm. | |
| From: Eric R. Scerri (The Periodic Table [2007], 04 'Nature') | |
| A reaction: I'm not sure I can make sense of this gulf between the metaphysical and the material realm, so this was an account heading for disaster. |
| 17406 | Moseley, using X-rays, showed that atomic number ordered better than atomic weight [Scerri] |
| Full Idea: By using X-rays, Henry Moseley later discovered that a better ordering principle for the periodic system is atomic numbers rather than atomic weight, by subjecting many different elements to bombardment. | |
| From: Eric R. Scerri (The Periodic Table [2007], 06 'Intro') | |
| A reaction: Moseley was killed in the First World War at the age of 26. It is interesting that they more or less worked out the whole table, before they discovered the best principle on which to found it. |
| 17408 | Some suggested basing the new periodic table on isotopes, not elements [Scerri] |
| Full Idea: Some chemists even suggested that the periodic table would have to be abandoned in favor of a classification system that included a separate place for every single isotope. | |
| From: Eric R. Scerri (The Periodic Table [2007], 06 'Intro') | |
| A reaction: The extreme case is tin, which has 21 isotopes, so is tin a fundamental, or is each of the isotopes a fundamental? Does there have to be a right answer to that? All tin isotopes basically react in the same way, so we stick with the elements table. |
| 17412 | Elements are placed in the table by the number of positive charges - the atomic number [Scerri] |
| Full Idea: The serial number of an element in the periodic table, its atomic number, corresponds to the number of positive charges in the atom. | |
| From: Eric R. Scerri (The Periodic Table [2007], 07 'Models') | |
| A reaction: Note that this is a feature of the nucleus, despite that fact that the electrons decide the chemical properties. A nice model for Locke's views on essentialism. |
| 17413 | Elements in the table are grouped by having the same number of outer-shell electrons [Scerri] |
| Full Idea: The modern notion is that atoms fall into the same group of the periodic table if they possess the same numbers of outer-shell electrons. | |
| From: Eric R. Scerri (The Periodic Table [2007], 07 'Quantum') | |
| A reaction: Scerri goes on to raise questions about this, on p.242. By this principle helium should be an alkaline earth element, but it isn't. |
| 17416 | Orthodoxy says the periodic table is explained by quantum mechanics [Scerri] |
| Full Idea: The prevailing reductionist climate implies that quantum mechanics inevitably provides a more fundamental explanation for the periodic system. | |
| From: Eric R. Scerri (The Periodic Table [2007], 08 'Concl') | |
| A reaction: Scerri has argued that chemists did much better than physicists in working out how the outer electron shells of atoms worked, by induction from data, rather than inference from basic principles. |
| 17414 | Pauli explained the electron shells, but not the lengths of the periods in the table [Scerri] |
| Full Idea: Pauli explained the maximum number of electrons successive shells can accommodate, ...but it does not explain the lengths of the periods, which is the really crucial property of the periodic table. | |
| From: Eric R. Scerri (The Periodic Table [2007], 07 'Pauli') | |
| A reaction: Paulis' Exclusion Principle says no two electrons in an atom can have the same set of four quantum numbers. He added 'spin' as a fourth number. It means 'electrons cannot be distinguished' (243). Scerri says the big problem is still not fully explained. |
| 17410 | Moseley showed the elements progress in units, and thereby clearly identified the gaps [Scerri] |
| Full Idea: Moseley's work showed that the successive elements in the periodic table have an atomic number greater by one unit. The gaps could then be identified definitively, as 43, 61, 72, 75, 85, 87, and 91. | |
| From: Eric R. Scerri (The Periodic Table [2007], 06 'Henry') | |
| A reaction: [compressed] |
| 17395 | Elements were ordered by equivalent weight; later by atomic weight; finally by atomic number [Scerri] |
| Full Idea: Historically, the ordering of elements across periods was determined by equivalent weight, then later by atomic weight, and eventually by atomic number. | |
| From: Eric R. Scerri (The Periodic Table [2007], 01 'React') | |
| A reaction: So they used to be ordered by quantities (measured by real numbers), but eventually were ordered by unit items (counted by natural numbers). There need to be distinct protons (unified) to be counted. |
| 17422 | The best classification needs the deepest and most general principles of the atoms [Scerri] |
| Full Idea: An optimal classification can be obtained by identifying the deepest and most general principles that govern the atoms of the elements. | |
| From: Eric R. Scerri (The Periodic Table [2007], 10 'Continuum') | |
| A reaction: He adds (p.286) that the best system will add the 'greatest degree of regularity' to these best principles. |
| 17419 | Since 99.96% of the universe is hydrogen and helium, the periodic table hardly matters [Scerri] |
| Full Idea: All the elements other than hydrogen and helium make up just 0.04% of the universe. Seen from this perspective, the periodic table appears to rather insignificant. | |
| From: Eric R. Scerri (The Periodic Table [2007], 10 'Astro') |
| 17417 | To explain the table, quantum mechanics still needs to explain order of shell filling [Scerri] |
| Full Idea: The order of shell filling has not yet been deduced from first principles, and this issue cannot be avoided if one is to really ask whether quantum mechanics explains the periodic system in a fundamental manner. | |
| From: Eric R. Scerri (The Periodic Table [2007], 09 'From') |
| 279 | Only divine things can always stay the same, and bodies are not like that [Plato] |
| Full Idea: It is fitting for only the most divine things of all to be always the same and in the same state and in the same respects, and the nature of body is not of this ordering. | |
| From: Plato (The Statesman [c.356 BCE], 269b) |