73 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. |
16985 | Possible worlds allowed the application of set-theoretic models to modal logic [Kripke] |
Full Idea: The main and the original motivation for the 'possible worlds analysis' - and the way it clarified modal logic - was that it enabled modal logic to be treated by the same set theoretic techniques of model theory used successfully in extensional logic. | |
From: Saul A. Kripke (Naming and Necessity preface [1980], p.19 n18) | |
A reaction: So they should be ascribed the same value that we attribute to classical model theory, whatever that is. |
11211 | If a sound conclusion comes from two errors that cancel out, the path of the argument must matter [Rumfitt] |
Full Idea: If a designated conclusion follows from the premisses, but the argument involves two howlers which cancel each other out, then the moral is that the path an argument takes from premisses to conclusion does matter to its logical evaluation. | |
From: Ian Rumfitt ("Yes" and "No" [2000], II) | |
A reaction: The drift of this is that our view of logic should be a little closer to the reasoning of ordinary language, and we should rely a little less on purely formal accounts. |
11210 | Standardly 'and' and 'but' are held to have the same sense by having the same truth table [Rumfitt] |
Full Idea: If 'and' and 'but' really are alike in sense, in what might that likeness consist? Some philosophers of classical logic will reply that they share a sense by virtue of sharing a truth table. | |
From: Ian Rumfitt ("Yes" and "No" [2000]) | |
A reaction: This is the standard view which Rumfitt sets out to challenge. |
11212 | The sense of a connective comes from primitively obvious rules of inference [Rumfitt] |
Full Idea: A connective will possess the sense that it has by virtue of its competent users' finding certain rules of inference involving it to be primitively obvious. | |
From: Ian Rumfitt ("Yes" and "No" [2000], III) | |
A reaction: Rumfitt cites Peacocke as endorsing this view, which characterises the logical connectives by their rules of usage rather than by their pure semantic value. |
16982 | A man has two names if the historical chains are different - even if they are the same! [Kripke] |
Full Idea: Two totally distinct 'historical chains' that be sheer accident assign the same name to the same man should probably count as creating distinct names despite the identity of the referents. | |
From: Saul A. Kripke (Naming and Necessity preface [1980], p.08 n9) | |
A reaction: A nice puzzle for his own theory. 'What's you name?' 'Alice, and Alice!' |
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. |
16981 | With the necessity of self-identity plus Leibniz's Law, identity has to be an 'internal' relation [Kripke] |
Full Idea: It is clear from (x)□(x=x) and Leibniz's Law that identity is an 'internal' relation: (x)(y)(x=y ⊃ □x=y). What pairs (w,y) could be counterexamples? Not pairs of distinct objects, …nor an object and itself. | |
From: Saul A. Kripke (Naming and Necessity preface [1980], p.03) | |
A reaction: I take 'internal' to mean that the necessity of identity is intrinsic to the item(s), and not imposed by some other force. |
4942 | The indiscernibility of identicals is as self-evident as the law of contradiction [Kripke] |
Full Idea: It seems to me that the Leibnizian principle of the indiscernibility of identicals (not to be confused with the identity of indiscernibles) is as self-evident as the law of contradiction. | |
From: Saul A. Kripke (Naming and Necessity preface [1980], p.03) | |
A reaction: This seems obviously correct, as it says no more than that a thing has whatever properties it has. If a difference is discerned, either you have made a mistake, or it isn't identical. |
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'. |
16984 | I don't think possible worlds reductively reveal the natures of modal operators etc. [Kripke] |
Full Idea: I do not think of 'possible worlds' as providing a reductive analysis in any philosophically significant sense, that is, as uncovering the ultimate nature, from either an epistemological or a metaphysical view, of modal operators, propositions etc. | |
From: Saul A. Kripke (Naming and Necessity preface [1980], p.19 n18) | |
A reaction: I think this remark opens the door for Kit Fine's approach, of showing what modality is by specifying its sources. Possible worlds model the behaviour of modal inferences. |
9385 | The very act of designating of an object with properties gives knowledge of a contingent truth [Kripke] |
Full Idea: If a speaker introduced a designator into a language by a ceremony, then in virtue of his very linguistic act, he would be in a position to say 'I know that Fa', but nevertheless 'Fa' would be a contingent truth (provided F is not an essential property). | |
From: Saul A. Kripke (Naming and Necessity preface [1980], p.14) | |
A reaction: If someone else does the designation, I seem to have contingent knowledge that the ceremony has taken place. You needn't experience the object, but you must experience the ceremony, even if you perform it. |
4943 | Instead of talking about possible worlds, we can always say "It is possible that.." [Kripke] |
Full Idea: We should remind ourselves the 'possible worlds' terminology can always be replaced by modal talk, such as "It is possible that…" | |
From: Saul A. Kripke (Naming and Necessity preface [1980], p.15) | |
A reaction: Coming from an originator of the possible worlds idea, this is a useful reminder that we don't have to get too excited about the ontological commitments involved. It may be just a 'way to talk', and hence a tool, rather than a truth about reality. |
16983 | Probability with dice uses possible worlds, abstractions which fictionally simplify things [Kripke] |
Full Idea: In studying probabilities with dice, we are introduced at a tender age to a set of 36 (miniature) possible worlds, if we (fictively) ignore everything except the two dice. …The possibilities are abstract states of the dice, not physical entities. | |
From: Saul A. Kripke (Naming and Necessity preface [1980], p.16) | |
A reaction: Interesting for the introduction by the great man of the words 'fictional' and 'abstract' into the discussion. He says elsewhere that he takes worlds to be less than real, but more than mere technical devices. |
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. |
11214 | We learn 'not' along with affirmation, by learning to either affirm or deny a sentence [Rumfitt] |
Full Idea: The standard view is that affirming not-A is more complex than affirming the atomic sentence A itself, with the latter determining its sense. But we could learn 'not' directly, by learning at once how to either affirm A or reject A. | |
From: Ian Rumfitt ("Yes" and "No" [2000], IV) | |
A reaction: [compressed] This seems fairly anti-Fregean in spirit, because it looks at the psychology of how we learn 'not' as a way of clarifying what we mean by it, rather than just looking at its logical behaviour (and thus giving it a secondary role). |
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. |
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. |
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. |
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'. |