109 ideas
| 6779 | Instrumentalists say distinctions between observation and theory vanish with ostensive definition [Bird] |
| Full Idea: Instrumentalists treat the theoretical/non-theoretical and the observational/non-observational distinctions as the same, ..because they think words get their meaning by way of ostensive definition. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.4) | |
| A reaction: To be honest, I'm not sure I quite understand this, but it sounds interesting... Ostensive definition seems to match the pragmatic spirit of instrumentalism (for which, see Idea 6778). Bird explains it all more fully. |
| 224 | When questions are doubtful we should concentrate not on objects but on ideas of the intellect [Plato] |
| Full Idea: Doubtful questions should not be discussed in terms of visible objects or in relation to them, but only with reference to ideas conceived by the intellect. | |
| From: Plato (Parmenides [c.364 BCE], 135e) |
| 232 | Opposites are as unlike as possible [Plato] |
| Full Idea: Opposites are as unlike as possible. | |
| From: Plato (Parmenides [c.364 BCE], 159a) |
| 8937 | Plato's 'Parmenides' is the greatest artistic achievement of the ancient dialectic [Hegel on Plato] |
| Full Idea: Plato's 'Parmenides' is the greatest artistic achievement of the ancient dialectic. | |
| From: comment on Plato (Parmenides [c.364 BCE]) by Georg W.F.Hegel - Phenomenology of Spirit Pref 71 | |
| A reaction: It is a long way from the analytic tradition of philosophy to be singling out a classic text for its 'artistic' achievement. Eventually we may even look back on, say, Kripke's 'Naming and Necessity' and see it in that light. |
| 8623 | Proof reveals the interdependence of truths, as well as showing their certainty [Euclid, by Frege] |
| Full Idea: Euclid gives proofs of many things which anyone would concede to him without question. ...The aim of proof is not merely to place the truth of a proposition beyond doubt, but also to afford us insight into the dependence of truths upon one another. | |
| From: report of Euclid (Elements of Geometry [c.290 BCE]) by Gottlob Frege - Grundlagen der Arithmetik (Foundations) §02 | |
| A reaction: This connects nicely with Shoemaker's view of analysis (Idea 8559), which I will adopt as my general view. I've always thought of philosophy as the aspiration to wisdom through the cartography of concepts. |
| 13907 | If you pick an arbitrary triangle, things proved of it are true of all triangles [Euclid, by Lemmon] |
| Full Idea: Euclid begins proofs about all triangles with 'let ABC be a triangle', but ABC is not a proper name. It names an arbitrarily selected triangle, and if that has a property, then we can conclude that all triangles have the property. | |
| From: report of Euclid (Elements of Geometry [c.290 BCE]) by E.J. Lemmon - Beginning Logic 3.2 | |
| A reaction: Lemmon adds the proviso that there must be no hidden assumptions about the triangle we have selected. You must generalise the properties too. Pick a triangle, any triangle, say one with three angles of 60 degrees; now generalise from it. |
| 13986 | Plato found antinomies in ideas, Kant in space and time, and Bradley in relations [Plato, by Ryle] |
| Full Idea: Plato (in 'Parmenides') shows that the theory that 'Eide' are substances, and Kant that space and time are substances, and Bradley that relations are substances, all lead to aninomies. | |
| From: report of Plato (Parmenides [c.364 BCE]) by Gilbert Ryle - Are there propositions? 'Objections' |
| 14150 | Plato's 'Parmenides' is perhaps the best collection of antinomies ever made [Russell on Plato] |
| Full Idea: Plato's 'Parmenides' is perhaps the best collection of antinomies ever made. | |
| From: comment on Plato (Parmenides [c.364 BCE]) by Bertrand Russell - The Principles of Mathematics §337 |
| 6297 | Euclid's geometry is synthetic, but Descartes produced an analytic version of it [Euclid, by Resnik] |
| Full Idea: Euclid's geometry is a synthetic geometry; Descartes supplied an analytic version of Euclid's geometry, and we now have analytic versions of the early non-Euclidean geometries. | |
| From: report of Euclid (Elements of Geometry [c.290 BCE]) by Michael D. Resnik - Maths as a Science of Patterns One.4 | |
| A reaction: I take it that the original Euclidean axioms were observations about the nature of space, but Descartes turned them into a set of pure interlocking definitions which could still function if space ceased to exist. |
| 9603 | An assumption that there is a largest prime leads to a contradiction [Euclid, by Brown,JR] |
| Full Idea: Assume a largest prime, then multiply the primes together and add one. The new number isn't prime, because we assumed a largest prime; but it can't be divided by a prime, because the remainder is one. So only a larger prime could divide it. Contradiction. | |
| From: report of Euclid (Elements of Geometry [c.290 BCE]) by James Robert Brown - Philosophy of Mathematics Ch.1 | |
| A reaction: Not only a very elegant mathematical argument, but a model for how much modern logic proceeds, by assuming that the proposition is false, and then deducing a contradiction from it. |
| 9894 | A unit is that according to which each existing thing is said to be one [Euclid] |
| Full Idea: A unit is that according to which each existing thing is said to be one. | |
| From: Euclid (Elements of Geometry [c.290 BCE], 7 Def 1) | |
| A reaction: See Frege's 'Grundlagen' §29-44 for a sustained critique of this. Frege is good, but there must be something right about the Euclid idea. If I count stone, paper and scissors as three, each must first qualify to be counted as one. Psychology creeps in. |
| 8738 | Postulate 2 says a line can be extended continuously [Euclid, by Shapiro] |
| Full Idea: Euclid's Postulate 2 says the geometer can 'produce a finite straight line continuously in a straight line'. | |
| From: report of Euclid (Elements of Geometry [c.290 BCE]) by Stewart Shapiro - Thinking About Mathematics 4.2 | |
| A reaction: The point being that this takes infinity for granted, especially if you start counting how many points there are on the line. The Einstein idea that it might eventually come round and hit you on the back of the head would have charmed Euclid. |
| 22278 | Euclid relied on obvious properties in diagrams, as well as on his axioms [Potter on Euclid] |
| Full Idea: Euclid's axioms were insufficient to derive all the theorems of geometry: at various points in his proofs he appealed to properties that are obvious from the diagrams but do not follow from the stated axioms. | |
| From: comment on Euclid (Elements of Geometry [c.290 BCE]) by Michael Potter - The Rise of Analytic Philosophy 1879-1930 03 'aim' | |
| A reaction: I suppose if the axioms of a system are based on self-evidence, this would licence an appeal to self-evidence elsewhere in the system. Only pedants insist on writing down what is obvious to everyone! |
| 8673 | Euclid's parallel postulate defines unique non-intersecting parallel lines [Euclid, by Friend] |
| Full Idea: Euclid's fifth 'parallel' postulate says if there is an infinite straight line and a point, then there is only one straight line through the point which won't intersect the first line. This axiom is independent of Euclid's first four (agreed) axioms. | |
| From: report of Euclid (Elements of Geometry [c.290 BCE]) by Michèle Friend - Introducing the Philosophy of Mathematics 2.2 | |
| A reaction: This postulate was challenged in the nineteenth century, which was a major landmark in the development of modern relativist views of knowledge. |
| 10250 | Euclid needs a principle of continuity, saying some lines must intersect [Shapiro on Euclid] |
| Full Idea: Euclid gives no principle of continuity, which would sanction an inference that if a line goes from the outside of a circle to the inside of circle, then it must intersect the circle at some point. | |
| From: comment on Euclid (Elements of Geometry [c.290 BCE]) by Stewart Shapiro - Philosophy of Mathematics 6.1 n2 | |
| A reaction: Cantor and Dedekind began to contemplate discontinuous lines. |
| 10302 | Euclid says we can 'join' two points, but Hilbert says the straight line 'exists' [Euclid, by Bernays] |
| Full Idea: Euclid postulates: One can join two points by a straight line; Hilbert states the axiom: Given any two points, there exists a straight line on which both are situated. | |
| From: report of Euclid (Elements of Geometry [c.290 BCE]) by Paul Bernays - On Platonism in Mathematics p.259 |
| 14157 | Modern geometries only accept various parts of the Euclid propositions [Russell on Euclid] |
| Full Idea: In descriptive geometry the first 26 propositions of Euclid hold. In projective geometry the 1st, 7th, 16th and 17th require modification (as a straight line is not a closed series). Those after 26 depend on the postulate of parallels, so aren't assumed. | |
| From: comment on Euclid (Elements of Geometry [c.290 BCE]) by Bertrand Russell - The Principles of Mathematics §388 |
| 1600 | Euclid's common notions or axioms are what we must have if we are to learn anything at all [Euclid, by Roochnik] |
| Full Idea: The best known example of Euclid's 'common notions' is "If equals are subtracted from equals the remainders are equal". These can be called axioms, and are what "the man who is to learn anything whatever must have". | |
| From: report of Euclid (Elements of Geometry [c.290 BCE], 72a17) by David Roochnik - The Tragedy of Reason p.149 |
| 16150 | One is, so numbers exist, so endless numbers exist, and each one must partake of being [Plato] |
| Full Idea: If one is, there must also necessarily be number - Necessarily - But if there is number, there would be many, and an unlimited multitude of beings. ..So if all partakes of being, each part of number would also partake of it. | |
| From: Plato (Parmenides [c.364 BCE], 144a) | |
| A reaction: This seems to commit to numbers having being, then to too many numbers, and hence to too much being - but without backing down and wondering whether numbers had being after all. Aristotle disagreed. |
| 229 | The one was and is and will be and was becoming and is becoming and will become [Plato] |
| Full Idea: The one was and is and will be and was becoming and is becoming and will become. | |
| From: Plato (Parmenides [c.364 BCE], 155d) |
| 21821 | Plato's Parmenides has a three-part theory, of Primal One, a One-Many, and a One-and-Many [Plato, by Plotinus] |
| Full Idea: The Platonic Parmenides is more exact [than Parmenides himself]; the distinction is made between the Primal One, a strictly pure Unity, and a secondary One which is a One-Many, and a third which is a One-and-Many. | |
| From: report of Plato (Parmenides [c.364 BCE]) by Plotinus - The Enneads 5.1.08 | |
| A reaction: Plotinus approves of this three-part theory. Parmenides has the problem that the highest Being contains no movement. By placing the One outside Being you can give it powers which an existent thing cannot have. Cf the concept of God. |
| 221 | Absolute ideas, such as the Good and the Beautiful, cannot be known by us [Plato] |
| Full Idea: The absolute good and the beautiful and all which we conceive to be absolute ideas are unknown to us. | |
| From: Plato (Parmenides [c.364 BCE], 134c) |
| 6780 | Anti-realism is more plausible about laws than about entities and theories [Bird] |
| Full Idea: There is anti-realism with regard to unobservable entities and the theories that purport to mention them, but the more plausible version attaches to theories concerning what laws of nature are. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.4) | |
| A reaction: This sounds right. I certainly find anti-realism about the entities of science utterly implausible. I also doubt whether there is any such thing as a law, above and beyond the behaviour of matter. Theories float between the two. |
| 227 | You must always mean the same thing when you utter the same name [Plato] |
| Full Idea: You must always mean the same thing when you utter the same name. | |
| From: Plato (Parmenides [c.364 BCE], 147d) |
| 223 | If you deny that each thing always stays the same, you destroy the possibility of discussion [Plato] |
| Full Idea: If a person denies that the idea of each thing is always the same, he will utterly destroy the power of carrying on discussion. | |
| From: Plato (Parmenides [c.364 BCE], 135c) |
| 210 | It would be absurd to think there were abstract Forms for vile things like hair, mud and dirt [Plato] |
| Full Idea: Are there abstract ideas for such things as hair, mud and dirt, which are particularly vile and worthless? That would be quite absurd. | |
| From: Plato (Parmenides [c.364 BCE], 130d) |
| 220 | The concept of a master includes the concept of a slave [Plato] |
| Full Idea: Mastership in the abstract is mastership of slavery in the abstract. | |
| From: Plato (Parmenides [c.364 BCE], 133e) |
| 211 | If admirable things have Forms, maybe everything else does as well [Plato] |
| Full Idea: It is troubling that if admirable things have abstract ideas, then perhaps everything else must have ideas as well. | |
| From: Plato (Parmenides [c.364 BCE], 130d) |
| 219 | If absolute ideas existed in us, they would cease to be absolute [Plato] |
| Full Idea: None of the absolute ideas exists in us, because then it would no longer be absolute. | |
| From: Plato (Parmenides [c.364 BCE], 133c) |
| 228 | Greatness and smallness must exist, to be opposed to one another, and come into being in things [Plato] |
| Full Idea: These two ideas, greatness and smallness, exist, do they not? For if they did not exist, they could not be opposites of one another, and could not come into being in things. | |
| From: Plato (Parmenides [c.364 BCE], 149e) |
| 16151 | Plato moves from Forms to a theory of genera and principles in his later work [Plato, by Frede,M] |
| Full Idea: It seems to me that Plato in the later dialogues, beginning with the second half of 'Parmenides', wants to substitute a theory of genera and theory of principles that constitute these genera for the earlier theory of forms. | |
| From: report of Plato (Parmenides [c.364 BCE]) by Michael Frede - Title, Unity, Authenticity of the 'Categories' V | |
| A reaction: My theory is that the later Plato came under the influence of the brilliant young Aristotle, and this idea is a symptom of it. The theory of 'principles' sounds like hylomorphism to me. |
| 218 | Participation is not by means of similarity, so we are looking for some other method of participation [Plato] |
| Full Idea: Participation is not by means of likeness, so we must seek some other method of participation. | |
| From: Plato (Parmenides [c.364 BCE], 133a) |
| 212 | The whole idea of each Form must be found in each thing which participates in it [Plato] |
| Full Idea: The whole idea of each form (of beauty, justice etc) must be found in each thing which participates in it. | |
| From: Plato (Parmenides [c.364 BCE], 131a) |
| 213 | Each idea is in all its participants at once, just as daytime is a unity but in many separate places at once [Plato] |
| Full Idea: Just as day is in many places at once, but not separated from itself, so each idea might be in all its participants at once. | |
| From: Plato (Parmenides [c.364 BCE], 131b) |
| 216 | If things are made alike by participating in something, that thing will be the absolute idea [Plato] |
| Full Idea: That by participation in which like things are made like, will be the absolute idea, will it not? | |
| From: Plato (Parmenides [c.364 BCE], 132e) |
| 215 | If things partake of ideas, this implies either that everything thinks, or that everything actually is thought [Plato] |
| Full Idea: If all things partake of ideas, must either everything be made of thoughts and everything thinks, or everything is thought, and so can't think? | |
| From: Plato (Parmenides [c.364 BCE], 132c) |
| 217 | Nothing can be like an absolute idea, because a third idea intervenes to make them alike (leading to a regress) [Plato] |
| Full Idea: It is impossible for anything to be like an absolute idea, because a third idea will appear to make them alike, and if that is like anything, it will lead to another idea, and so on. | |
| From: Plato (Parmenides [c.364 BCE], 133a) |
| 214 | If absolute greatness and great things are seen as the same, another thing appears which makes them seem great [Plato] |
| Full Idea: If you regard the absolute great and the many great things in the same way, will not another appear beyond, by which all these must appear to be great? | |
| From: Plato (Parmenides [c.364 BCE], 132a) |
| 15851 | Parts must belong to a created thing with a distinct form [Plato] |
| Full Idea: The part would not be the part of many things or all, but of some one character ['ideas'] and of some one thing, which we call a 'whole', since it has come to be one complete [perfected] thing composed [created] of all. | |
| From: Plato (Parmenides [c.364 BCE], 157d) | |
| A reaction: A serious shot by Plato at what identity is. Harte quotes it (125) and shows that 'character' is Gk 'idea', and 'composed' will translate as 'created'. 'Form' links this Platonic passage to Aristotle's hylomorphism. |
| 15846 | In Parmenides, if composition is identity, a whole is nothing more than its parts [Plato, by Harte,V] |
| Full Idea: At the heart of the 'Parmenides' puzzles about composition is the thesis that composition is identity. Considered thus, a whole adds nothing to an ontology that already includes its parts | |
| From: report of Plato (Parmenides [c.364 BCE]) by Verity Harte - Plato on Parts and Wholes 2.5 | |
| A reaction: There has to be more to a unified identity that mere proximity of the parts. When do parts come together, and when do they actually 'compose' something? |
| 15849 | Plato says only a one has parts, and a many does not [Plato, by Harte,V] |
| Full Idea: In 'Parmenides' it is argued that a part cannot be part of a many, but must be part of something one. | |
| From: report of Plato (Parmenides [c.364 BCE], 157c) by Verity Harte - Plato on Parts and Wholes 3.2 | |
| A reaction: This looks like the right way to go with the term 'part'. We presuppose a unity before we even talk of its parts, so we can't get into contradictions and paradoxes about their relationships. |
| 15850 | Anything which has parts must be one thing, and parts are of a one, not of a many [Plato] |
| Full Idea: The whole of which the parts are parts must be one thing composed of many; for each of the parts must be part, not of a many, but of a whole. | |
| From: Plato (Parmenides [c.364 BCE], 157c) | |
| A reaction: This is a key move of metaphysics, and we should hang on to it. The other way madness lies. |
| 13259 | It seems that the One must be composed of parts, which contradicts its being one [Plato] |
| Full Idea: The One must be composed of parts, both being a whole and having parts. So on both grounds the One would thus be many and not one. But it must be not many, but one. So if the One will be one, it will neither be a whole, nor have parts. | |
| From: Plato (Parmenides [c.364 BCE], 137c09), quoted by Kathrin Koslicki - The Structure of Objects 5.2 | |
| A reaction: This is the starting point for Plato's metaphysical discussion of objects. It seems to begin a line of thought which is completed by Aristotle, surmising that only an essential structure can bestow identity on a bunch of parts. |
| 15847 | Two things relate either as same or different, or part of a whole, or the whole of the part [Plato] |
| Full Idea: Everything is surely related to everything as follows: either it is the same or different; or, if it is not the same or different, it would be related as part to whole or as whole to part. | |
| From: Plato (Parmenides [c.364 BCE], 146b) | |
| A reaction: This strikes me as a really helpful first step in trying to analyse the nature of identity. Two things are either two or (actually) one, or related mereologically. |
| 6796 | Subjective probability measures personal beliefs; objective probability measures the chance of an event happening [Bird] |
| Full Idea: Subjective probability measures a person's strength of belief in the truth of a proposition; objective probability concerns the chance a certain sort of event has of happening, independently of whether anyone thinks it is likely to occur or not. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.6) | |
| A reaction: The challenge to the second one is that God would know for certain whether a meteor will hit the Earth next week. The impact looks like 'bad luck' to us, but necessary to one who really knows. |
| 6797 | Objective probability of tails measures the bias of the coin, not our beliefs about it [Bird] |
| Full Idea: In tossing a coin, the objective probability of tails is a measure of the bias of the coin; the bias and the probability are objective features of the coin, like its mass and shape; these properties have nothing to do with our beliefs about the coin. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.6) | |
| A reaction: Despite my reservation that God would not seem to be very interested in the probabilities of coin-tossing, since he knows each outcome with certaintly, this is fairly convincing. God might say that the coin has a 'three-to-two bias'. |
| 6800 | Many philosophers rate justification as a more important concept than knowledge [Bird] |
| Full Idea: Many philosophers take the notion of justification to be more important or more basic than the concept of knowledge. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.7) | |
| A reaction: Intriguing. Given the obvious social and conventional element in 'knowledge' ("do we agree that the candidate really knows the answer?"), justification may well be closer to where the real action is. 'Logos', after all, is at the heart of philosophy. |
| 6786 | As science investigates more phenomena, the theories it needs decreases [Bird] |
| Full Idea: A remarkable fact about modern science is that as the number of phenomena which science has investigated has grown, the number of theories needed to explain them has decreased. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.4) | |
| A reaction: This rebuts the idea that theories are probably false because we are unlikely to have thought of the right one (Idea 6784). More data suggests more theories, yet we end up with fewer theories. Why is simplification of theories possible? |
| 6792 | If theories need observation, and observations need theories, how do we start? [Bird] |
| Full Idea: If we cannot know the truth of theories without observation, and we cannot know the truth of observations without theories, where do we start? | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.5) | |
| A reaction: See Idea 6793. You make a few observations, under the illusion that they are objective, then formulate a promising theory, then go back and deconstruct the observations, then tighten up the theory, and so on. |
| 6757 | Explanation predicts after the event; prediction explains before the event [Bird] |
| Full Idea: Explanation is prediction after the event and prediction is explanation before the event. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.2) | |
| A reaction: A nice slogan, fitting Hempel's 'covering law' view of explanation. It doesn't seem quite right, because explanations and predictions are couched in very different language. Prediction implies an explanation; explanation implies a prediction. |
| 6805 | Relativity ousted Newtonian mechanics despite a loss of simplicity [Bird] |
| Full Idea: The theories of relativity ousted Newtonian mechanics despite a loss of simplicity. | |
| From: Alexander Bird (Philosophy of Science [1998]) | |
| A reaction: This nicely demonstrates that simplicity is not essential, even if it is desirable. The point applies to the use of Ockham's Razor (Idea 6806), and to Hume's objection to miracles (Idea 2227), where strange unnatural events may be the truth. |
| 6777 | Realists say their theories involve truth and the existence of their phenomena [Bird] |
| Full Idea: A realist says of their theories that they can be evaluated according to truth, they aim at truth, their success favours their truth, their unobserved entities probably exist, and they would explain the observable phenomena. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.4) | |
| A reaction: This seems to me to be the only sensible attitude towards scientific theories, even if they do become confusing down at the level of quantum theory. Theories aim to be true explanations. |
| 6804 | There is no agreement on scientific method - because there is no such thing [Bird] |
| Full Idea: I find little concurrence as to what scientific method might actually be - the reason being, I conclude, that there is no such thing. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.8) | |
| A reaction: I take the essence of science to be two things: first, becoming very fussy about empirical evidence; second, setting up controlled conditions to get at the evidence that seems to be needed. I agree that there seems to be no distinctive way of thinking. |
| 6778 | Instrumentalists regard theories as tools for prediction, with truth being irrelevant [Bird] |
| Full Idea: Instrumentalism is so called because it regards theories not as attempts to describe or explain the world, but as instruments for making predictions; for the instrumentalist, asking about the truth of a theory is a conceptual mistake. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.4) | |
| A reaction: It cannot be denied that theories are used to make predictions, and there is nothing wrong with being solely interested in predictions. I cannot make head or tail of the idea that truth is irrelevant. Why is a given theory so successful? |
| 6775 | Induction is inference to the best explanation, where the explanation is a law [Bird] |
| Full Idea: Induction can be seen as inference to the best explanation, where the explanation is a law. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.3) | |
| A reaction: I like this. I increasingly think of explanation as central to rational thought, as the key route for empiricists to go beyond their immediate and verifiable experience. Laws can be probabilistic. |
| 6791 | If Hume is right about induction, there is no scientific knowledge [Bird] |
| Full Idea: If Hume is right about induction then there is no scientific knowledge. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.5) | |
| A reaction: The first step is to recognise that induction is not deductively valid, but that does not make it irrational. If something happens five times, get ready for the sixth. If we discover the necessary features of nature, we can predict the future. |
| 6790 | Anything justifying inferences from observed to unobserved must itself do that [Bird] |
| Full Idea: Whatever could do the job of justifying an inference from the observed to the unobserved must itself be an inference from the observed to the unobserved. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.5) | |
| A reaction: We must first accept that the unobserved might not be like the observed, no matter how much regularity we have, so it can't possibly be a logical 'inference'. Essences generate regularities, but non-essences may not. |
| 6738 | Any conclusion can be drawn from an induction, if we use grue-like predicates [Bird] |
| Full Idea: It looks as if any claim about the future can be made to be a conclusion of an inductive argument from any premises about the past, as long as we use a strange enough grue-like predicate. | |
| From: Alexander Bird (Philosophy of Science [1998], Intro) | |
| A reaction: So don't use strange grue-like predicates. If all our predicates randomly changed their reference each day, we would be unable to talk to one another at all. Emeralds don't change their colour-properties, so why change the predicates that refer to them? |
| 6739 | Several months of observing beech trees supports the deciduous and evergreen hypotheses [Bird] |
| Full Idea: If someone were to observe beech trees every day over one summer they would have evidence that seems to support both the hypothesis that beech trees are deciduous and the hypothesis that they are evergreens. | |
| From: Alexander Bird (Philosophy of Science [1998], Intro) | |
| A reaction: Bird offers this to anyone who (like me) is tempted to dismiss the 'grue' problem as ridiculous. Obviously he is right; 'deciduous' works like 'grue'. But we invented the predicate 'deciduous' to match an observed property. |
| 6799 | We normally learn natural kinds from laws, but Goodman shows laws require prior natural kinds [Bird] |
| Full Idea: We know what natural kinds there are by seeing which properties appear in the laws of nature. But one lesson of Goodman's problem is that we cannot identify the laws of nature without some prior identification of natural kinds. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.7) | |
| A reaction: For Goodman's problem, see Idea 4783. The essentialist view is that the natural kinds come first, and the so-called 'laws' are just regularities in events that arise from the interaction of stable natural kinds. (Keep predicates and properties separate). |
| 6798 | Bayesianism claims to find rationality and truth in induction, and show how science works [Bird] |
| Full Idea: Keen supporters of Bayesianism say it can show how induction is rational and can lead to truth, and it can reveal the underlying structure of actual scientific reasoning. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.6) | |
| A reaction: See Idea 2798 for Bayes' Theorem. I find it intuitively implausible that our feeling for probabilities could be reduced to precise numbers, given the subjective nature of the numbers we put into the equation. |
| 6752 | The objective component of explanations is the things that must exist for the explanation [Bird] |
| Full Idea: There is an 'objective', non-epistemic component to explanations, consisting of the things that must exist for A to be able to explain B, and the relations those things have to one another. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.2) | |
| A reaction: There seems to be some question-begging here, in that you have to decide what explanation you are after before you can decide which existences are of interest. There are objective facts, though, about what causally links to what. |
| 6754 | We talk both of 'people' explaining things, and of 'facts' explaining things [Bird] |
| Full Idea: We talk both of 'people' explaining things, and of 'facts' explaining things. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.2) | |
| A reaction: An important point, and it is the job of philosophers to pull the two apart. How we talk does not necessarily show how it is. The concept of explanation is irrelevant in a universe containing no minds, or one containing only God. People seek the facts. |
| 6750 | Explanations are causal, nomic, psychological, psychoanalytic, Darwinian or functional [Bird] |
| Full Idea: Explanations can be classified as causal, nomic, psychological, psychoanalytic, Darwinian and functional. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.2) | |
| A reaction: These could be subdivided, perhaps according to different types of cause. Personally, being a reductionist (like David Lewis, see Idea 3989), I suspect that all of these explanations could be reduced to causation. Essences explain causes. |
| 6761 | Contrastive explanations say why one thing happened but not another [Bird] |
| Full Idea: A 'contrastive explanation' explains why one thing happened but not another. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.2) | |
| A reaction: If I explain why the ship sank, is this contrastive, or just causal, or both? Am I explaining why it sank rather than turned into a giraffe? An interesting concept, but I can't see myself making use of it. |
| 6758 | 'Covering law' explanations only work if no other explanations are to be found [Bird] |
| Full Idea: The fact that something fits the 'covering law' model of explanation is no guarantee that it is an explanation, for that depends on what other explanations are there to be found. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.2) | |
| A reaction: He gives Achinstein's example of a poisoned man who is run over by a bus. It has to be a basic requirement of explanations that they are the 'best', and not just something that fits a formula. |
| 6759 | Livers always accompany hearts, but they don't explain hearts [Bird] |
| Full Idea: All animals with a liver also have a heart; so we can deduce from this plus the existence of Fido's liver that he also has a heart, but his liver does not explain why he has a heart. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.2) | |
| A reaction: This is a counterexample to Hempel's deductive-nomological view of explanation. It seems a fairly decisive refutation of any attempt to give a simple rule for explaining things. Different types of explanation compete, and there is a subjective element. |
| 6756 | Probabilistic-statistical explanations don't entail the explanandum, but makes it more likely [Bird] |
| Full Idea: The probabilistic-statistical view of explanation (also called inductive-statistical explantion) is similar to deductive-nomological explanation, but instead of entailing the explanandum a probabilistic-statistical explantion makes it very likely. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.2) | |
| A reaction: If people have umbrellas up, does that explain rain? Does the presence of a psychopath in the audience explain why I don't go to a rock concert? Still, it has a point. |
| 6760 | An operation might reduce the probability of death, yet explain a death [Bird] |
| Full Idea: An operation for cancer might lead to a patient's death, and so it explains the patient's death while at the same time reducing the probability of death. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.2) | |
| A reaction: This attacks Hempel's 'covering law' approach. Increasing probability of something clearly does not necessarily explain it, though it often will. Feeding you contaminated food will increase the probability of your death, and may cause it. |
| 6785 | Inference to the Best Explanation is done with facts, so it has to be realist [Bird] |
| Full Idea: Explanation of a fact is some other fact or set of facts. And so Inference to the Best Explanation is inference to facts; someone who employs it cannot but take a realist attitude to a theory which is preferred on these grounds. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.4) | |
| A reaction: So my personal commitment to abduction is entailed by my realism, and my realism is entailed by my belief in the possibility of abduction. We can't explain the properties of a table just by referring to our experiences of tables. |
| 6788 | Maybe bad explanations are the true ones, in this messy world [Bird] |
| Full Idea: It is objected to 'best explanation' that this may well not be the best of all possible worlds - so why think that the best explanation is true? Maybe bad (complicated, unsystematic and weak) explanations are true. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.4) | |
| A reaction: The only rebuttal of this objection to best explanation seems to be a priori. It would just seem an odd situation if very simple explanations fitted the facts and yet were false, like the points on a graph being a straight line by pure coincidence. |
| 6787 | Which explanation is 'best' is bound to be subjective, and no guide to truth [Bird] |
| Full Idea: It is objected to 'best explanation' that beauty is in the eye of the beholder - the goodness of possible explanations is subjective, and so the choice of best explanation is also subjective, and hence not a suitable guide to truth. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.4) | |
| A reaction: Explanation is indeed dependent both on the knowledge of the person involved, and on their interests. That doesn't, though, mean that you can choose any old explanation. Causal networks are features of the world. |
| 6751 | Maybe explanation is so subjective that it cannot be a part of science [Bird] |
| Full Idea: Some philosophers have thought that explanation is hopelessly subjective, so subjective even that it is should have no part in proper science. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.2) | |
| A reaction: God requires no explanations, and children require many. If fundamental explanations are causal, then laying bare the causal chains is the explanation, whether you want it or not. God knows all the explanations. See Idea 6752. |
| 222 | Only a great person can understand the essence of things, and an even greater person can teach it [Plato] |
| Full Idea: Only a man of very great natural gifts will be able to understand that everything has a class and absolute essence, and an even more wonderful man can teach this. | |
| From: Plato (Parmenides [c.364 BCE], 135a) |
| 225 | The unlimited has no shape and is endless [Plato] |
| Full Idea: The unlimited partakes neither of the round nor of the straight, because it has no ends nor edges. | |
| From: Plato (Parmenides [c.364 BCE], 137e) |
| 233 | Some things do not partake of the One [Plato] |
| Full Idea: The others cannot partake of the one in any way; they can neither partake of it nor of the whole. | |
| From: Plato (Parmenides [c.364 BCE], 159d) | |
| A reaction: Compare Idea 231 |
| 2062 | The only movement possible for the One is in space or in alteration [Plato] |
| Full Idea: If the One moves it either moves spatially or it is altered, since these are the only motions. | |
| From: Plato (Parmenides [c.364 BCE], 138b) |
| 231 | Everything partakes of the One in some way [Plato] |
| Full Idea: The others are not altogether deprived of the one, for they partake of it in some way. | |
| From: Plato (Parmenides [c.364 BCE], 157c) | |
| A reaction: Compare Idea 233. |
| 6776 | Natural kinds are those that we use in induction [Bird] |
| Full Idea: Natural kinds are the kinds one should make use of in inductive inference (if that is explanation which leads to laws). | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.3) | |
| A reaction: The problem with this is that it is epistemological rather than ontological. In induction we use superficial resemblences that are immediately obvious, whereas the nature of kinds can be buried deep in the chemistry or physics. |
| 6767 | Rubies and sapphires are both corundum, with traces of metals varying their colours [Bird] |
| Full Idea: Both rubies (valuable) and sapphires (less valuable) are corundum (Al2O3), differing only in their colours, for which traces of iron, titanium and chomium are responsible. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.3) | |
| A reaction: A nice example which illustrates how natural kinds determined by nominal essence could be drastically different from those suggested by real essence. It certainly suggests that corundum might be a natural kind, but ruby isn't. |
| 6768 | Tin is not one natural kind, but appears to be 21, depending on isotope [Bird] |
| Full Idea: If real essences are decided by microstructure, then what we call the element tin is not a natural kind, but a mixture of 21 different kinds, one for each isotope. There also exist two different allotropes of tin - white tin and grey tin. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.3) | |
| A reaction: This example vividly brings out the difficulties of the Kripke-Putnam view. If natural kinds 'overlap', then there would be a very extensive overlap among the 21 isotopes of tin. |
| 6770 | Membership of a purely random collection cannot be used as an explanation [Bird] |
| Full Idea: One might randomly collect diverse things and give the collection a name, but one would not expect it to explain anything to say that a certain object belonged to this collection. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.3) | |
| A reaction: This is in support of Bird's view that natural kinds are formulated because of their explanatory role. There is, though, an undeniable subjective aspect to explanation, in that explanations arise from the ignorance and interests of persons. |
| 6771 | Natural kinds may overlap, or be sub-kinds of one another [Bird] |
| Full Idea: It seems clear that in some cases one natural kind may be a subkind of another, while in other cases natural kinds may overlap without one being the subkind of another. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.3) | |
| A reaction: Given the enormous difficulty of pinpointing natural kinds (e.g. Idea 6768), it is hard to know whether the comment is correct or not. Ellis says natural kinds come 'in hierarchies', which would make subkinds normal, but overlapping unlikely. |
| 6773 | If F is a universal appearing in a natural law, then Fs form a natural kind [Bird] |
| Full Idea: The proposal is that if F is a universal appearing in some natural law, then Fs form a natural kind. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.3) | |
| A reaction: Such proposals always invite the question 'What is it about F that enables it to be a universal in a natural law?' Nothing can be ultimately defined simply by its role. The character (essence, even) of the thing makes the role possible. |
| 6769 | In the Kripke-Putnam view only nuclear physicists can know natural kinds [Bird] |
| Full Idea: In the Kripke-Putnam view, it is very difficult for anyone except nuclear physicists to pick out natural kinds, since everything else is made out of compounds of different isotopes. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.3) | |
| A reaction: The concept of a rigid 'natural kind' does not have to be sacred. Tin might be considered a natural kind, despite having 21 isotopes. What matters is protons, not the neutrons. |
| 6774 | Darwinism suggests that we should have a native ability to detect natural kinds [Bird] |
| Full Idea: Creatures that are able to recognise natural kinds and laws have a selective advantage, so Darwinism suggests that we should have some native ability to detect natural kinds. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.3) | |
| A reaction: This seems right, but it makes 'natural kind' a rather instrumental concept, relative to our interests. True natural kinds cut across our interests, as when we discover by anatomy that whales are not fish, or that rubies and sapphires are both corundum. |
| 6764 | Nominal essence of a natural kind is the features that make it fit its name [Bird] |
| Full Idea: The nominal essence of a natural kind K consists of those features a thing must have to deserve the name 'a K' by virtue of the meaning of that name. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.3) | |
| A reaction: Some people think 'nominal essence' is the only essence there is, which would make it relative to human languages. The rival view is that there are 'real essences'. I favour the latter view. |
| 6766 | Jadeite and nephrite are superficially identical, but have different composition [Bird] |
| Full Idea: There might be more than one natural kind that shares the same superficial features, …jade, for example, has two forms, jadeite and nephrite, which are similar in superficial properties, but have different chemical composition and structure. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.3) | |
| A reaction: It might be questioned whether jadeite and nephrite really are natural kinds, either together or separately. |
| 6808 | Reference to scientific terms is by explanatory role, not by descriptions [Bird] |
| Full Idea: I propose that reference to scientific terms, such as natural kinds and theoretical terms, is not determined by a sense or description attached to the term, but by its explanatory role. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.8) | |
| A reaction: He gives the example of an electron, which had the same role in electrical theory, despite changes in understanding its nature. One might talk of its 'natural' (causal) role, rather than its 'explanatory' role (which implies a human viewpoint). |
| 6753 | Laws are more fundamental in science than causes, and laws will explain causes [Bird] |
| Full Idea: I think laws are fundamental and where there is a cause there is always a set of laws that encompasses the cause; identifying a cause will never be the final word in an scientific investigation, but will be open to supplementation by the underlying law. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.2) | |
| A reaction: I think this is wrong. I would say (from the essentialist angle) that essences have causes, and the laws are the regularities that are caused by the essences. If laws are the lowest level of explanation, why these laws and not others? God? |
| 6762 | Newton's laws cannot be confirmed individually, but only in combinations [Bird] |
| Full Idea: None of Newton's laws individually records anything that can be observed; it is only from combinations of Newton's laws that we can derive the measurable motions of bodies. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.2) | |
| A reaction: This certainly scuppers any traditional positivist approach to how we confirm laws of nature. It invites the possibility that a different combination might fit the same observations. Experiments attempt to isolate laws. |
| 6763 | Parapsychology is mere speculation, because it offers no mechanisms for its working [Bird] |
| Full Idea: Wegener's theory of continental drift was only accepted when the theory of plate tectonics was developed, providing a mechanism. While some correlations exist for parapsychology, lack of plausible mechanisms leaves it as speculation. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.2) | |
| A reaction: But parapsychology is not even on a par with Wegener's speculation, because his was consistent with known physical laws, whereas parapsychology flatly contradicts them. The so-called correlations are also not properly established. |
| 6772 | Existence requires laws, as inertia or gravity are needed for mass or matter [Bird] |
| Full Idea: I suspect that what we mean by 'mass' and 'matter' depends on our identifying the existence of laws of inertia and gravity; hence the idea of a world without laws is incoherent, for there to be anything at all there must be some laws and some kinds. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.3) | |
| A reaction: I find this counterintuitive. Reasonably stable existence requires something reasonably like laws. We only understand the physical world because we interact with it. But neither of those is remotely as strong as Bird's claim. |
| 6740 | 'All uranium lumps are small' is a law, but 'all gold lumps are small' is not [Bird] |
| Full Idea: 'Uranium lumps have mass of less than 1000 kg' is a law, but 'gold lumps have mass of less than 1000kg' is not a law. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.1) | |
| A reaction: A nice example. Essentialists talk about the nature of the substances; regularity theorists prefer to talk of nested or connected regularities (e.g. about explosions). In induction, how do you decide what your duty requires you to observe? |
| 6741 | There can be remarkable uniformities in nature that are purely coincidental [Bird] |
| Full Idea: Bode's non-law (of 1772, about the gaps between the planets) shows that there can be remarkable uniformities in nature that are purely coincidental. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.1) | |
| A reaction: If Bode's law really were confirmed, even for asteroids and newly discovered planets, it might suggest that an explanation really is required, and there is some underlying cause. How likely is the coincidence? Perhaps we have no way of telling. |
| 6742 | A law might have no instances, if it was about things that only exist momentarily [Bird] |
| Full Idea: A law might have no instances at all; for example, about the chemical and electrical behaviour of the transuranic elements, which only exist briefly in laboratories. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.1) | |
| A reaction: Nice example. We need to distinguish, though, (as Bird reminds us) between laws and theories. We have no theories in this area, but there are counterfactual truths about what the transuranic elements would do in certain circumstances. |
| 6743 | If laws are just instances, the law should either have gaps, or join the instances arbitrarily [Bird] |
| Full Idea: For the simple regularity theorist, the function ought to be a gappy one, leaving out values not actually instantiated; …one function would fit the actual points on the graph as well as any other. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.1) | |
| A reaction: The 'simple' theorist says there is nothing more to a law than its instances. Clearly Bird is right; if the points line up, we join them with a straight line, making counterfactual assumptions about points which were not actually observed. |
| 6744 | Where is the regularity in a law predicting nuclear decay? [Bird] |
| Full Idea: If a law of nuclear physics says that nuclei of a certain kind have a probability p of decaying within time t, what is the regularity here? | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.1) | |
| A reaction: Hume gives an answer, in terms of regularities observed among previous instances. Nevertheless the figure p given in the law does not itself have any instances, so the law is predicting something that may never have actually happened before. |
| 6747 | Laws cannot explain instances if they are regularities, as something can't explain itself [Bird] |
| Full Idea: It can be objected that laws cannot do the job of explaining their instances if they are merely regularities, ...because something cannot explain itself. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.1) | |
| A reaction: A nice point. The objection assumes that a law should explain things, rather than just describing them. I take the model to be smoking-and-cancer; the statistics describe what is happening, but only lung biochemistry will explain it. |
| 6746 | There may be many laws, each with only a few instances [Bird] |
| Full Idea: It might be that there is a large number of laws each of which has only a small number of instances. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.1) | |
| A reaction: This is a problem for the Ramsey-Lewis view (Idea 6745) that the laws of nature are a simple, powerful and coherent system. We must be cautious about bringing a priori principles like Ockham's Razor (Idea 3667) to bear on the laws of nature. |
| 6748 | Similar appearance of siblings is a regularity, but shared parents is what links them [Bird] |
| Full Idea: There may be a regularity of siblings looking similar, but the tie that binds them is not their similarity, but rather their being born of the same parents. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.1) | |
| A reaction: A nice objection to the regularity view. Regularities, as so often in philosophy (e.g. Idea 1364), may be the evidence or test for a law, rather than the law itself, which requires causal mechanisms, ultimately based (I think) in essences. |
| 6749 | We can only infer a true regularity if something binds the instances together [Bird] |
| Full Idea: We cannot infer a regularity from its instances unless there is something stronger than the regularity itself binding the instances together. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.1) | |
| A reaction: Spells out the implication of the example in Idea 6748. The reply to this criticism would be that no account can possibly be given of the 'something stronger' than further regularities, at a lower level (e.g. in the physics). |
| 6803 | If we only infer laws from regularities among observations, we can't infer unobservable entities. [Bird] |
| Full Idea: If the naïve inductivist says we should see well-established regularities among our observations, and take that to be the law or causal connection…this will not help us to infer the existence of unobservable entities. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.8) | |
| A reaction: The obvious solution to this difficulty is an appeal to 'best explanation'. Bird is obviously right that we couldn't survive in the world, let alone do science, if we only acted on what we had actually observed (e.g. many bodies, but not the poison). |
| 6801 | Accidental regularities are not laws, and an apparent regularity may not be actual [Bird] |
| Full Idea: Many actual regularities are not laws (accidental regularities), and many perceived regularities are not actual ones (a summer's worth of observing green leaves). | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.8) | |
| A reaction: These problems are not sufficient to refute the regularity view of laws. Accidental regularities can only be short-lived, and perceived regularities support laws without clinching them. There is an awful lot of regularity behind laws concerning gravity. |
| 6745 | A regularity is only a law if it is part of a complete system which is simple and strong [Bird] |
| Full Idea: The systematic (Ramsey-Lewis) regularity theory says that a regularity is a law of nature if and only if it appears as a theorem or axiom in that true deductive system which achieves a best combination of simplicity and strength. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.1) | |
| A reaction: Personally I don't accept the regularity view of laws, but this looks like the best account anyone has come up with. Individual bunches of regularities can't add up to or demonstrate a law, but coherence with all regularities might do it. |
| 6802 | With strange enough predicates, anything could be made out to be a regularity [Bird] |
| Full Idea: We learned from Goodman's problem that with strange enough predicates anything could be made out to be a regularity. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.8) | |
| A reaction: For Goodman's problem, see Idea 4783. The point, as I see it, is that while predicates can be applied arbitrarily (because they are just linguistic), properties cannot, because they are features of the world. Emeralds are green. |
| 6789 | If flame colour is characteristic of a metal, that is an empirical claim needing justification [Bird] |
| Full Idea: I might say that flame colours are a characteristic feature of metals, but this is an empirical proposition which is in part about the unobserved, and stands in need of justification. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.5) | |
| A reaction: This draws attention to the fact that essentialism is not just a metaphysical theory, but is also part of the scientific enterprise. Among things to research about metals is the reason why they have a characteristic flame. |
| 6807 | In Newton mass is conserved, but in Einstein it can convert into energy [Bird] |
| Full Idea: According to Newton mass is conserved, while in Einstein's theory mass is not conserved but can be converted into and from energy. | |
| From: Alexander Bird (Philosophy of Science [1998]) | |
| A reaction: Perhaps this is the most fundamental difference between the theories. It certainly suggests that 'mass' was a conventional concept rather than a natural one. Maybe the relative notion of 'weight' is more natural than 'mass'. |
| 234 | We couldn't discuss the non-existence of the One without knowledge of it [Plato] |
| Full Idea: There must be knowledge of the one, or else not even the meaning of the words 'if the one does not exist' would be known. | |
| From: Plato (Parmenides [c.364 BCE], 160d) |