Combining Philosophers

All the ideas for Susan A. Gelman, Karl Popper and R Kaplan / E Kaplan

unexpand these ideas     |    start again     |     specify just one area for these philosophers


54 ideas

2. Reason / A. Nature of Reason / 5. Objectivity
Scientific objectivity lies in inter-subjective testing [Popper]
     Full Idea: The objectivity of scientific statements lies in the fact that they can be inter-subjectively tested.
     From: Karl Popper (The Logic of Scientific Discovery [1934], p.22), quoted by Reiss,J/Spreger,J - Scientific Objectivity 2.4
     A reaction: Does this mean that objectivity is the same as consensus? A bunch of subjective prejudiced fools can reach a consensus. And in the middle of that bunch there can be one person who is objecfive. Sounds wrong.
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / j. Axiom of Choice IX
Using Choice, you can cut up a small ball and make an enormous one from the pieces [Kaplan/Kaplan]
     Full Idea: The problem with the Axiom of Choice is that it allows an initiate (by an ingenious train of reasoning) to cut a golf ball into a finite number of pieces and put them together again to make a globe as big as the sun.
     From: R Kaplan / E Kaplan (The Art of the Infinite [2003], 9)
     A reaction: I'm not sure how this works (and I think it was proposed by the young Tarski), but it sounds like a real problem to me, for all the modern assumptions that Choice is fine.
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / b. Types of number
1 and 0, then add for naturals, subtract for negatives, divide for rationals, take roots for irrationals [Kaplan/Kaplan]
     Full Idea: You have 1 and 0, something and nothing. Adding gives us the naturals. Subtracting brings the negatives into light; dividing, the rationals; only with a new operation, taking of roots, do the irrationals show themselves.
     From: R Kaplan / E Kaplan (The Art of the Infinite [2003], 1 'Mind')
     A reaction: The suggestion is constructivist, I suppose - that it is only operations that produce numbers. They go on to show that complex numbers don't quite fit the pattern.
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / g. Real numbers
The rationals are everywhere - the irrationals are everywhere else [Kaplan/Kaplan]
     Full Idea: The rationals are everywhere - the irrationals are everywhere else.
     From: R Kaplan / E Kaplan (The Art of the Infinite [2003], 1 'Nameless')
     A reaction: Nice. That is, the rationals may be dense (you can always find another one in any gap), but the irrationals are continuous (no gaps).
6. Mathematics / A. Nature of Mathematics / 4. Using Numbers / f. Arithmetic
'Commutative' laws say order makes no difference; 'associative' laws say groupings make no difference [Kaplan/Kaplan]
     Full Idea: The 'commutative' laws say the order in which you add or multiply two numbers makes no difference; ...the 'associative' laws declare that regrouping couldn't change a sum or product (e.g. a+(b+c)=(a+b)+c ).
     From: R Kaplan / E Kaplan (The Art of the Infinite [2003], 2 'Tablets')
     A reaction: This seem utterly self-evident, but in more complex systems they can break down, so it is worth being conscious of them.
'Distributive' laws say if you add then multiply, or multiply then add, you get the same result [Kaplan/Kaplan]
     Full Idea: The 'distributive' law says you will get the same result if you first add two numbers, and then multiply them by a third, or first multiply each by the third and then add the results (i.e. a · (b+c) = a · b + a · c ).
     From: R Kaplan / E Kaplan (The Art of the Infinite [2003], 2 'Tablets')
     A reaction: Obviously this will depend on getting the brackets right, to ensure you are indeed doing the same operations both ways.
7. Existence / E. Categories / 2. Categorisation
Even fairly simple animals make judgements based on categories [Gelman]
     Full Idea: All organisms form categories: even mealworms have category-based preferences, and higher-order animals such as pigeons or octopi can display quite sophisticated categorical judgements.
     From: Susan A. Gelman (The Essential Child [2003], 01 'Prelims')
     A reaction: [She cites some 1980 research to support this] This comes as no surprise, as I take categorisation as almost definitive of what a mind is. My surmise is that some sort of 'labelling' system is at the heart of it (like Googlemail labels!).
Children accept real stable categories, with nonobvious potential that gives causal explanations [Gelman]
     Full Idea: By five children assume that a variety of categories have rich inductive potential, are stable over outward transformations, include crucial nonobvious properties, have innate potential, privilege causal features, can be explained causally, and are real.
     From: Susan A. Gelman (The Essential Child [2003], 06 'Intro')
     A reaction: This is Gelman's helpful summary of the findings of research on childhood essentialising, and says the case for this phenomenon is 'compelling'.
8. Modes of Existence / C. Powers and Dispositions / 7. Against Powers
Propensities are part of a situation, not part of the objects [Popper]
     Full Idea: Propensities should not be regarded as inherent in an object, such as a die or a penny, but should be regarded as inherent in a situation (of which, of course, the object was part).
     From: Karl Popper (A World of Propensities [1993], p.14), quoted by George Molnar - Powers 6.2
     A reaction: Molnar argues against this claim, and I agree with him. We can see why Popper might prefer this relational view, given that powers often only become apparent in unusual relational situations.
9. Objects / D. Essence of Objects / 1. Essences of Objects
In India, upper-castes essentialize caste more than lower-castes do [Gelman]
     Full Idea: The notion of caste in India is more essentialized among upper-caste than lower-caste individuals.
     From: Susan A. Gelman (The Essential Child [2003], 08 'Intro')
     A reaction: In a book defending fairly innate essentialism in the human race, Gelman offers this point as a warning that large cultural ingredients can be involved. Racism is the classic difficulty with essentialism.
Essentialism is either natural to us, or an accident of our culture, or a necessary result of language [Gelman]
     Full Idea: The two views contrasting with essentialism naturally emerging in childhood are the claim that essentialism is a historical accident emerging from Western philosophy, and that essentialism is an inherent consequence of naming things.
     From: Susan A. Gelman (The Essential Child [2003], 01 'Background')
     A reaction: Helpful. I take Idea 15682 to rule out the idea that it is just a feature of western culture. I can't conceive of early man surviving without essentialism. I don't think it rules out the naming view. Animals may do what emerges in us as full 'naming'.
Children's concepts include nonobvious features, like internal parts, functions and causes [Gelman]
     Full Idea: Children incorporate a variety of nonobvious features into their concepts, including internal parts, functions, causes, and ontological distinctions.
     From: Susan A. Gelman (The Essential Child [2003], 01 'Prelims')
     A reaction: This remark sums up the general thesis of her book, which she supports with a wealth of first-hand evidence. It supports my view, that the desire and need for explanation is at the root of essentialist concepts. It's hard wired in us.
9. Objects / D. Essence of Objects / 2. Types of Essence
Essentialism: real or representational? sortal, causal or ideal? real particulars, or placeholders? [Gelman]
     Full Idea: We map types of essentialism by asking is it in the world or in our representations, is it sortal or causal or ideal, and is it specific particulars or placeholders for the unknown?
     From: Susan A. Gelman (The Essential Child [2003], 01 'Prelims')
     A reaction: I am struck by the way that this practising experimental psychologist gets to ask questions and make distinctions much more extensively than most armchair philosophers on the subject. She focuses on the representational, causal, placeholder view.
9. Objects / D. Essence of Objects / 5. Essence as Kind
Essentialism says categories have a true hidden nature which gives an object its identity [Gelman]
     Full Idea: Essentialism is the view that categories have an underlying reality or true nature that one cannot observe directly but that gives an object its identity.
     From: Susan A. Gelman (The Essential Child [2003], 01 'Intro')
     A reaction: I think the introduction of categories here is a misunderstanding. Does an uncategorisable thing therefore have no identity (even though it has properties)? If categories give objects their identity, what gives categories their identity?
Sortals are needed for determining essence - the thing must be categorised first [Gelman]
     Full Idea: I suggest that sortals are likewise required for determining essence. One cannot answer the question 'What is the essence of this?' without supplying the sortal - of this 'what'.
     From: Susan A. Gelman (The Essential Child [2003], 01 'Prelims')
     A reaction: I remain baffled by this view. I take the category to be an inductive generalisation from other similar individuals. It can't get off the ground if you don't start with the individuals. Sortals are just a shorthand.
Kind (unlike individual) essentialism assumes preexisting natural categories [Gelman]
     Full Idea: With kind essentialism the person assumes that the world is divided up into preexisting natural categories. Individual essentialism seems not to require any such commitment to kind realism.
     From: Susan A. Gelman (The Essential Child [2003], 06 'Essentialism')
     A reaction: This pinpoints my difficulty: how do we decide whether some category or attributed essence is part of a preexisting natural kind? Some natural kinds are self-evident, like water (roughly), but others need subtle teasing out. How is the teasing done?
9. Objects / D. Essence of Objects / 7. Essence and Necessity / c. Essentials are necessary
Kinship is essence that comes in degrees, and age groups are essences that change over time [Gelman]
     Full Idea: Kinship is essentialized, but admits of degrees, ...and people can be essentialist even about categories they do not view as fixed over time, such as age groupings.
     From: Susan A. Gelman (The Essential Child [2003], 03 'Summary')
     A reaction: Given my notion of essence are necessarily explanatory, I embrace both of these points. Being very athletic comes in degrees, and changes over times.
9. Objects / D. Essence of Objects / 11. Essence of Artefacts
Human artefacts may have essences, in their purposes [Popper]
     Full Idea: One might adopt the view that certain things of our own making, such as clocks, may well be said to have 'essences', viz. their 'purposes', and what makes them serve these purposes.
     From: Karl Popper (Conjectures and Refutations [1963], 3.3 n17)
     A reaction: This is from one of the arch-opponents of essentialism. Could we take him on a slippery slope into essences for evolved creatures, or their organs? His argument says admitting an essence for a clock prevents using it for another purpose.
9. Objects / D. Essence of Objects / 14. Knowledge of Essences
Essentialism comes from the cognitive need to categorise [Gelman]
     Full Idea: Essentialism has its source in the cognitive requirement of categorization in certain domains - particularly as they affect the young learner.
     From: Susan A. Gelman (The Essential Child [2003], 01 'Essentialist')
     A reaction: I think the phenomenon is better understood as part of the cognitive requirement to understand and explain. Categorisation is just one way to aid explanation. Children try to understand (essentially) a new animal without categorisation.
We found no evidence that mothers teach essentialism to their children [Gelman]
     Full Idea: We found no evidence that mothers teach essentialism to their children. ...Mothers teach children about kinds, not about essences, and mothers help children identify which categories are richly structured.
     From: Susan A. Gelman (The Essential Child [2003], 07 'Conclusions')
     A reaction: This is a psychologist who specialises in this topic. If you think essentialism is inculcated by a our culture, you will have to blame the fathers.
9. Objects / D. Essence of Objects / 15. Against Essentialism
Popper felt that ancient essentialism was a bar to progress [Popper, by Mautner]
     Full Idea: Karl Popper vehemently rejected the essentialism which underpins Plato and Aristotle, taking it to be a major obstacle to political, moral and scientific progress.
     From: report of Karl Popper (Open Society and Its Enemies:Hegel and Marx [1945]) by Thomas Mautner - Penguin Dictionary of Philosophy p.179
     A reaction: This makes Popper sound like an existentialist, which seems unlikely. Modern essentialism would say the opposite about science - that hunting for external imposed laws is a red herring, and we should try to understand essences.
Essentialism is useful for predictions, but it is not the actual structure of reality [Gelman]
     Full Idea: Essentialism is a reasoning heuristic that allows us to make fairly good predictions much of the time, but it should not be confused with the structure of reality.
     From: Susan A. Gelman (The Essential Child [2003], 11 'Discussion')
     A reaction: She particularly cites biology as the area where it might be inaccurate. I'm beginning to think that the operations of induction are the place to look for an good understanding of essentialism.
9. Objects / E. Objects over Time / 12. Origin as Essential
Peope favor historical paths over outward properties when determining what something is [Gelman]
     Full Idea: People favor historical paths over outward properties when determining what something is. ...An object looking like a knife is less likely to be called 'a knife' if it is described as having been created by accident.
     From: Susan A. Gelman (The Essential Child [2003], 06 'Essentialism')
     A reaction: I like this because it talks, suggestively, of 'historical paths' rather than of 'origin'. Thus we might judge a person's identity by their traumatic experience rather than by their birth. This doesn't challenge necessity of origin, but affects labels.
11. Knowledge Aims / A. Knowledge / 2. Understanding
There is intentional, mechanical, teleological, essentialist, vitalist and deontological understanding [Gelman]
     Full Idea: The modes of understanding (or modes of construal) which have been proposed are intentional, mechanical, teleological, essentialist, vitalist (perhaps), and deontological.
     From: Susan A. Gelman (The Essential Child [2003], 11 'Broadening')
     A reaction: She cites psychological research to support this, and calls it 'a relatively small number' of modes. Compare Aristotle's four modes of cause/explanation.
12. Knowledge Sources / E. Direct Knowledge / 4. Memory
Memories often conform to a theory, rather than being neutral [Gelman]
     Full Idea: Memory is notorious for conforming to theory (rather than memory being a neutral source of information).
     From: Susan A. Gelman (The Essential Child [2003], 09 'Theory')
     A reaction: This observation by a psychologist is music to sceptics about objectivity. Memory is so fundamental to our basic epistemology that it could even be the nature of thought itself.
14. Science / A. Basis of Science / 6. Falsification
Give Nobel Prizes for really good refutations? [Gorham on Popper]
     Full Idea: Popper implies that we should be giving Nobel Prizes to scientists who use severe tests to show us what the world is not like!
     From: comment on Karl Popper (The Logic of Scientific Discovery [1934]) by Geoffrey Gorham - Philosophy of Science 2
     A reaction: A lovely simple point. The refuters are important members of the scientific team, but not the leaders.
Particulars can be verified or falsified, but general statements can only be falsified (conclusively) [Popper]
     Full Idea: Whereas particular reality statements are in principle completely verifiable or falsifiable, things are different for general reality statements: they can indeed be conclusively falsified, they can acquire a negative truth value, but not a positive one.
     From: Karl Popper (Two Problems of Epistemology [1932], p.256), quoted by J. Alberto Coffa - The Semantic Tradition from Kant to Carnap 18 'Laws'
     A reaction: This sounds like a logician's approach to science, but I prefer to look at coherence, where very little is actually conclusive, and one tinkers with the theory instead.
Falsification is the criterion of demarcation between science and non-science [Popper, by Magee]
     Full Idea: According to Popper, falsification is the criterion of demarcation between science and non-science.
     From: report of Karl Popper (The Logic of Scientific Discovery [1934]) by Bryan Magee - Popper Ch.3
     A reaction: If I propose something which might be falsified in a hundred years, is it science NOW? Suppose my theory appeared to be falsifiable, but (after much effort) it turned out not to be? Suppose I just see a pattern (like quark theory) in a set of facts?
We don't only reject hypotheses because we have falsified them [Lipton on Popper]
     Full Idea: Popper's mistake is to hold that disconfirmation and elimination work exclusively through refutation.
     From: comment on Karl Popper (The Logic of Scientific Discovery [1934]) by Peter Lipton - Inference to the Best Explanation (2nd) 05 'Explanation'
     A reaction: The point is that we reject hypotheses even if they have not actually been refuted, on the grounds that they don't give a good explanation. I agree entirely with Lipton.
If falsification requires logical inconsistency, then probabilistic statements can't be falsified [Bird on Popper]
     Full Idea: In Popper's sense of the word 'falsify', whereby an observation statement falsifies a hypothesis only by being logically inconsistent with it, nothing can ever falsify a probabilistic or statistical hypothesis, which is therefore unscientific.
     From: comment on Karl Popper (The Logic of Scientific Discovery [1934]) by Alexander Bird - Philosophy of Science Ch.5
     A reaction: In general, no prediction can be falsified until the events occur. This seems to be Aristotle's 'sea fight' problem (Idea 1703).
When Popper gets in difficulties, he quietly uses induction to help out [Bird on Popper]
     Full Idea: It is a feature of Popper's philosophy that when the going gets tough, induction is quietly called upon to help out.
     From: comment on Karl Popper (The Logic of Scientific Discovery [1934]) by Alexander Bird - Philosophy of Science Ch.5
     A reaction: This appears to be the central reason for the decline in Popper's reputation as the saviour of science. It would certainly seem absurd to say that you know nothing when you have lots of verification but not a glimmer of falsification.
14. Science / B. Scientific Theories / 2. Aim of Science
Good theories have empirical content, explain a lot, and are not falsified [Popper, by Newton-Smith]
     Full Idea: Popper's principles are roughly that one theory is superior to another if it has greater empirical content, if it can account for the successes of the first theory, and if it has not been falsified (unlike the first theory).
     From: report of Karl Popper (The Logic of Scientific Discovery [1934]) by W.H. Newton-Smith - The Rationality of Science I.6
14. Science / C. Induction / 1. Induction
Inductive success is rewarded with more induction [Gelman]
     Full Idea: Inductive success is rewarded with more induction.
     From: Susan A. Gelman (The Essential Child [2003], 11 'Broadening')
     A reaction: I love this one. Neat, accurate, and central to how we understand the world. I take inductive success to be stored as labels, concepts, categories, words and general truths, which are then our resource for further attempts.
14. Science / C. Induction / 3. Limits of Induction
Children overestimate the power of a single example [Gelman]
     Full Idea: We suggest that children overestimate the power of a single example.
     From: Susan A. Gelman (The Essential Child [2003], 06 'The role')
     A reaction: This conclusion arises from extensive psychological research. 'My grandma smoked, and she lived to be 97' - adults do this too. Wittgenstein says assuming other minds because of your own is induction from one example!
Children make errors in induction by focusing too much on categories [Gelman]
     Full Idea: Because of their narrow focus, children's sensitivity to categories as the basis of induction is a reasoning bias that, though useful much of the time, results in systematic errors.
     From: Susan A. Gelman (The Essential Child [2003], 06 'The role')
     A reaction: This is the bad sense of 'essentialism' which worries its opponents. Presumably, though, my favoured scientific essentialism will be 'scientific', and avoid this problem. The relation between categories and induction needs to be clear.
The first million numbers confirm that no number is greater than a million [Kaplan/Kaplan]
     Full Idea: The claim that no number is greater than a million is confirmed by the first million test cases.
     From: R Kaplan / E Kaplan (The Art of the Infinite [2003], 2 'Intro')
     A reaction: Extrapolate from this, and you can have as large a number of cases as you could possibly think of failing to do the inductive job. Love it! Induction isn't about accumulations of cases. It is about explanation, which is about essence. Yes!
There is no such thing as induction [Popper, by Magee]
     Full Idea: According to Popper, induction is a dispensable concept, a myth. It does not exist. There is no such thing.
     From: report of Karl Popper (The Logic of Scientific Discovery [1934]) by Bryan Magee - Popper Ch.2
     A reaction: This is a nice bold summary of the Popper view - that falsification is the underlying rational activity which we mistakenly think is verification by repeated observations. Put like this, Popper seems to be wrong. We obviously learn from experiences.
14. Science / C. Induction / 4. Reason in Induction
Science cannot be shown to be rational if induction is rejected [Newton-Smith on Popper]
     Full Idea: If Popper follows Hume in abandoning induction, there is no way in which he can justify the claims that there is growth of scientific knowledge and that science is a rational activity.
     From: comment on Karl Popper (The Logic of Scientific Discovery [1934]) by W.H. Newton-Smith - The Rationality of Science III.3
14. Science / D. Explanation / 1. Explanation / a. Explanation
People tend to be satisfied with shallow explanations [Gelman]
     Full Idea: People tend to be satisfied with rather shallow explanations.
     From: Susan A. Gelman (The Essential Child [2003], 06 'Is essentialism')
     A reaction: She cites some psychological research to support this. Pretty obvious really. I take the so-called 'scientific method' to be nothing more than ceasing to be satisfied with such shallowness.
14. Science / D. Explanation / 3. Best Explanation / b. Ultimate explanation
Science does not aim at ultimate explanations [Popper]
     Full Idea: I contest the essentialist doctrine that science aims at ultimate explanations, one which cannot be further explained, and which is in no need of any further explanation.
     From: Karl Popper (Conjectures and Refutations [1963], 3.3)
     A reaction: If explanations are causal, this seems to a plea for an infinite regress of causes, which is an odd thing to espouse. Are the explanations verbal descriptions or things in the world. There can be no perfect descriptions, but there may be ultimate things.
18. Thought / A. Modes of Thought / 4. Folk Psychology
Folk essentialism rests on belief in natural kinds, in hidden properties, and on words indicating structures [Gelman]
     Full Idea: The three components of essentialism as a folk belief are the idea that certain categories are natural kinds, the idea that some unobservable property causes the way things are, and the idea that words reflect real structures.
     From: Susan A. Gelman (The Essential Child [2003], 01 'Prelims')
18. Thought / D. Concepts / 3. Ontology of Concepts / a. Concepts as representations
Labels may indicate categories which embody an essence [Gelman]
     Full Idea: Labels may signal categories that are believed to embody an essence.
     From: Susan A. Gelman (The Essential Child [2003], 02 'Privileged')
     A reaction: This is quoted by her, as a summary of a substantial body of research which she endorses. I cite it because it pinpoints my own view. I take 'labels' to be basic to minds, as organisers of thought, and this ties essences to labels. Satisfying picture.
18. Thought / D. Concepts / 4. Structure of Concepts / a. Conceptual structure
Causal properties are seen as more central to category concepts [Gelman]
     Full Idea: Properties that enter into causally meaningful links are better remembered and are treated as more central to the category than properties that are not causally meaningful.
     From: Susan A. Gelman (The Essential Child [2003], 05 'Causation2')
     A reaction: This is a summary of considerable psychological research. This account not only sounds plausible, but would fit better withy why we form concepts and categories in the first place. We are trying to relate to the causations of nature.
18. Thought / D. Concepts / 4. Structure of Concepts / d. Concepts as prototypes
Categories are characterized by distance from a prototype [Gelman]
     Full Idea: On prototype views, categories are characterized by distance from a prototype.
     From: Susan A. Gelman (The Essential Child [2003], 05 'Causation')
     A reaction: Gelman observes that this view makes no reference to any causal features of things. This cuts them off from using underlying essences in the process of categorisation and concept-formation. How do you spot a prototype, with no category?
18. Thought / D. Concepts / 4. Structure of Concepts / f. Theory theory of concepts
Theory-based concepts use rich models to show which similarities really matter [Gelman]
     Full Idea: Theory-based approaches to categories are a response to the limitations of mere similarities holding the category together, and require knowledge-rich explanatory models to say which features are more central to a concept.
     From: Susan A. Gelman (The Essential Child [2003], 05 'Causation1')
     A reaction: I see a promising account in linking theory theory to essentialism. For a physical object (or even for a process) infer a structure, and then identify what is most important in that structure. That gives you your stable, agreed concept.
18. Thought / D. Concepts / 5. Concepts and Language / c. Concepts without language
Prelinguistic infants acquire and use many categories [Gelman]
     Full Idea: Language does not appear to be necessary for forming categories, since prelinguistic infants acquire many categories, and even use categories to form inferences about unknown properties.
     From: Susan A. Gelman (The Essential Child [2003], 08 'Intro')
     A reaction: She cites lots of research in support of this claim. The idea may come as a surprise to some people, but not to me. I take it that categorisation is what a brain is for, including animal brains.
26. Natural Theory / B. Natural Kinds / 3. Knowing Kinds
One sample of gold is enough, but one tree doesn't give the height of trees [Gelman]
     Full Idea: We can confidently determine the chemical composition of gold from just a single sample, but we cannot determine the height of trees from just a single tree.
     From: Susan A. Gelman (The Essential Child [2003], 06 'The role')
     A reaction: The tricky word here is 'confidently'. If you meet one Latvian who is nice, do you assume they are all nice? At what point do you decide gold etc. really are natural kinds, where one sample tells all? Evolution of species...
26. Natural Theory / B. Natural Kinds / 5. Reference to Natural Kinds
Nouns seem to invoke stable kinds more than predicates do [Gelman]
     Full Idea: Children judged personal characteristics as more stable when they were referred to by a noun ('She is a carrot eater') than by a verbal predicate ('She eats carrots whenever she can')
     From: Susan A. Gelman (The Essential Child [2003], 08 'Naming')
     A reaction: This fits with my feeling that 'labels' are the basis of how the mind works. The noun invokes a genuine category of thing, where a predicate attaches to some preselected category ('she'). Gelman says names encourage inductions.
26. Natural Theory / D. Laws of Nature / 8. Scientific Essentialism / a. Scientific essentialism
Galilean science aimed at true essences, as the ultimate explanations [Popper]
     Full Idea: The third of the Galilean doctrines of science is that the best, the truly scientific theories, describe the 'essences' or the 'essential natures' of things - the realities which lie behind the appearances. They are ultimate explanations.
     From: Karl Popper (Conjectures and Refutations [1963], 3.3)
     A reaction: This seems to be the seventeenth century doctrine which was undermined by Humeanism, and hence despised by Popper, but is now making a comeback, with a new account of essence and necessity.
Essentialism encourages us to think about the world scientifically [Gelman]
     Full Idea: Essentialism encourages a 'scientific' mindset in thinking about the natural world, a belief that intensive study of a natural domain will yield ever more underlying properties.
     From: Susan A. Gelman (The Essential Child [2003], 11 'Intro')
     A reaction: Maybe scientists must be committed to essences, the way mathematicians must be committed to numbers? This idea spendidly opposes the doubts expressed by Popper.
Essentialism doesn't mean we know the essences [Gelman]
     Full Idea: Essentialism does not entail that people know what the essence is.
     From: Susan A. Gelman (The Essential Child [2003], 09 'Theory')
     A reaction: This is a fundamental and (I would say) fairly obvious point, but it needs to be made to the more passionate opponents of essentialism.
26. Natural Theory / D. Laws of Nature / 8. Scientific Essentialism / d. Knowing essences
Essentialism starts from richly structured categories, leading to a search for underlying properties [Gelman]
     Full Idea: If my speculations are correct, then essentialism starts out strictly as a belief that many categories are richly structured kinds, then additionally becomes a search for underlying inherent properties.
     From: Susan A. Gelman (The Essential Child [2003], 10 'Figuring')
     A reaction: This is her summary of extensive essentialist research among children. She favours the priority of kinds and categories. We actually change taxonomies on the basis of revisions in our accounts of essence. Science negotiates.
26. Natural Theory / D. Laws of Nature / 8. Scientific Essentialism / e. Anti scientific essentialism
Essentialist views of science prevent further questions from being raised [Popper]
     Full Idea: The essentialist view of Newton (due to Roger Cotes) ...prevented fruitful questions from being raised, such as, 'What is the cause of gravity?' or 'Can we deduce Newton's theory from a more general independent theory?'
     From: Karl Popper (Conjectures and Refutations [1963], 3.3)
     A reaction: This is Popper's main (and only) objection to essentialism - that it is committed to ultimate explanations, and smugly terminates science when it thinks it has found them. This does not strike me as a problem with scientific essentialism.
A major objection to real essences is the essentialising of social categories like race, caste and occupation [Gelman]
     Full Idea: One major argument against the view that essences are real is the rampant essentializing of categories that are socially constructed (such as race, caste and occupation).
     From: Susan A. Gelman (The Essential Child [2003], 11 'Is essentialism')
     A reaction: You can't argue with that. It raises the question of whether the approach of scientific essentialism has any value in the social, rather than physical, sciences. We jokingly essentialise groups of people such as referees or Oxonians.