display all the ideas for this combination of texts
17 ideas
| 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. |