23 ideas
| 22764 | Ordinary speech is not exact about what is true; we say we are digging a well before the well exists [Sext.Empiricus] |
| Full Idea: We must allow ordinary speech to use inexact terms, as it does not seek after what is really true but what is supposed to be true. We speak of digging a well or weaving a cloak, but there is no well or cloak when they are being dug or woven. | |
| From: Sextus Empiricus (Against the Logicians (two books) [c.180], II.129) | |
| A reaction: Nice examples. The imprecision is reduced if I say I am creating a well, because that implies something that is not yet complete. If I say I intend to dig a well, is that imprecise because the well does not exist? |
| 3870 | The real problem of science is how to choose between possible explanations [Newton-Smith] |
| Full Idea: Once we move beyond investigating correlations between observables the question of what does or should guide our choice between alternative explanatory accounts becomes problematic. | |
| From: W.H. Newton-Smith (The Rationality of Science [1981], IX.2) |
| 3859 | We do not wish merely to predict, we also want to explain [Newton-Smith] |
| Full Idea: We do not wish merely to predict, we also want to explain. | |
| From: W.H. Newton-Smith (The Rationality of Science [1981], II.3) |
| 3853 | For science to be rational, we must explain scientific change rationally [Newton-Smith] |
| Full Idea: We are only justified in regarding scientific practice as the very paradigm of rationality if we can justify the claim that scientific change is rationally explicable. | |
| From: W.H. Newton-Smith (The Rationality of Science [1981], I.2) |
| 3854 | Positivists hold that theoretical terms change, but observation terms don't [Newton-Smith] |
| Full Idea: For positivists it was taken that while theory change meant change in the meaning of theoretical terms, the meaning of observational terms was invariant under theory change. | |
| From: W.H. Newton-Smith (The Rationality of Science [1981], I.4) |
| 3855 | Critics attack positivist division between theory and observation [Newton-Smith] |
| Full Idea: The critics of positivism attacked the conception of a dichotomy between theory and observation. | |
| From: W.H. Newton-Smith (The Rationality of Science [1981], I.4) |
| 3869 | More truthful theories have greater predictive power [Newton-Smith] |
| Full Idea: If a theory is a better approximation to the truth, then it is likely that it will have greater predictive power. | |
| From: W.H. Newton-Smith (The Rationality of Science [1981], VIII.8) |
| 3861 | Theories generate infinite truths and falsehoods, so they cannot be used to assess probability [Newton-Smith] |
| Full Idea: We cannot explicate a useful notion of verisimilitude in terms of the number of truths and the number of falsehoods generated by a theory, because they are infinite. | |
| From: W.H. Newton-Smith (The Rationality of Science [1981], III.4) |
| 22762 | Some properties are inseparable from a thing, such as the length, breadth and depth of a body [Sext.Empiricus] |
| Full Idea: Some properties are inseparable from the things to which they belong - as are length, breadth and depth from bodies, for without their presence it is impossible to perceive Body. | |
| From: Sextus Empiricus (Against the Logicians (two books) [c.180], I.270) | |
| A reaction: For the opposite case he suggests a man running, talking or sleeping. He doesn't mention essential natures, but this is clearly correct. We might say that they are properties which need to be mentioned in a full definition. |
| 3867 | De re necessity arises from the way the world is [Newton-Smith] |
| Full Idea: A necessary truth is 'de re' if its necessity arises from the way the world is. | |
| From: W.H. Newton-Smith (The Rationality of Science [1981], VII.6) |
| 3872 | We must assess the truth of beliefs in identifying them [Newton-Smith] |
| Full Idea: We cannot determine what someone's beliefs are independently of assessing to some extent the truth or falsity of the beliefs. | |
| From: W.H. Newton-Smith (The Rationality of Science [1981], X.4) |
| 22759 | Fools, infants and madmen may speak truly, but do not know [Sext.Empiricus] |
| Full Idea: The fool and the infant and the madman at times say something true, but they do not possess knowledge of the true. | |
| From: Sextus Empiricus (Against the Logicians (two books) [c.180], I.042) | |
| A reaction: This may be correct of someone who is insane, but seems unfair to the fool and the infant. At what age do children begin to know things? If speech was just random nonsense, an accidental truth seems impossible. |
| 22760 | Madmen are reliable reporters of what appears to them [Sext.Empiricus] |
| Full Idea: The madman is a trustworthy criterion of the appearances which occur in madness. | |
| From: Sextus Empiricus (Against the Logicians (two books) [c.180], I.062) | |
| A reaction: It is hard to conceive of an genuinely insane person deliberately misreporting their hallucinations. They are, of course, the sole witness. |
| 3857 | Defeat relativism by emphasising truth and reference, not meaning [Newton-Smith] |
| Full Idea: The challenge of incommensurability can be met once it is realised that in comparing theories the notions of truth and reference are more important than that of meaning. | |
| From: W.H. Newton-Smith (The Rationality of Science [1981], I.6) |
| 3858 | A full understanding of 'yellow' involves some theory [Newton-Smith] |
| Full Idea: A full grasp of the concept '…is yellow' involves coming to accept as true bits of theory; that is, generalisations involving the term 'yellow'. | |
| From: W.H. Newton-Smith (The Rationality of Science [1981], II.2) |
| 3862 | All theories contain anomalies, and so are falsified! [Newton-Smith] |
| Full Idea: According to Feyerabend all theories are born falsified, because no theory has ever been totally free of anomalies. | |
| From: W.H. Newton-Smith (The Rationality of Science [1981], III.9) |
| 3863 | The anomaly of Uranus didn't destroy Newton's mechanics - it led to Neptune's discovery [Newton-Smith] |
| Full Idea: When scientists observed the motion of Uranus, they did not give up on Newtonian mechanics. Instead they posited the existence of Neptune. | |
| From: W.H. Newton-Smith (The Rationality of Science [1981], III.9) |
| 3864 | Anomalies are judged against rival theories, and support for the current theory [Newton-Smith] |
| Full Idea: Whether to reject an anomaly has to be decided on the basis of the availability of a rival theory, and on the basis of the positive evidence for the theory in question. | |
| From: W.H. Newton-Smith (The Rationality of Science [1981], III.9) |
| 3865 | Why should it matter whether or not a theory is scientific? [Newton-Smith] |
| Full Idea: Why should it be so important to distinguish between theories that are scientific and those that are not? | |
| From: W.H. Newton-Smith (The Rationality of Science [1981], IV.3) |
| 3866 | If theories are really incommensurable, we could believe them all [Newton-Smith] |
| Full Idea: If theories are genuinely incommensurable why should I be faced with the problem of choosing between them? Why not believe them all? | |
| From: W.H. Newton-Smith (The Rationality of Science [1981], VII.1) |
| 17613 | We should judge principles by the science, not science by some fixed principles [Zermelo] |
| Full Idea: Principles must be judged from the point of view of science, and not science from the point of view of principles fixed once and for all. Geometry existed before Euclid's 'Elements', just as arithmetic and set theory did before Peano's 'Formulaire'. | |
| From: Ernst Zermelo (New Proof of Possibility of Well-Ordering [1908], §2a) | |
| A reaction: This shows why the axiomatisation of set theory is an ongoing and much-debated activity. |
| 22763 | We can only dream of a winged man if we have experienced men and some winged thing [Sext.Empiricus] |
| Full Idea: He who in his sleep dreams of a winged man does not dream so without having seen some winged thing and a man. And in general it is impossible to find in conception anything which one does not possess as known by experience. | |
| From: Sextus Empiricus (Against the Logicians (two books) [c.180], II.058) | |
| A reaction: This precisely David Hume's empiricist account of the formation of concepts. Hume's example is a golden mountain, which he got from Aquinas. How do we dream of faces we have never encountered, or shapes we have never seen? |
| 3871 | Explaining an action is showing that it is rational [Newton-Smith] |
| Full Idea: To explain an action as an action is to show that it is rational. | |
| From: W.H. Newton-Smith (The Rationality of Science [1981], X.2) |