14 ideas
| 9565 | Zermelo made 'set' and 'member' undefined axioms [Zermelo, by Chihara] |
| Full Idea: The terms 'set' and 'is a member of' are primitives of Zermelo's 1908 axiomatization of set theory. They are not given model-theoretic analyses or definitions. | |
| From: report of Ernst Zermelo (works [1920]) by Charles Chihara - A Structural Account of Mathematics 7.5 | |
| A reaction: This looks like good practice if you want to work with sets, but not so hot if you are interested in metaphysics. |
| 3339 | For Zermelo's set theory the empty set is zero and the successor of each number is its unit set [Zermelo, by Blackburn] |
| Full Idea: For Zermelo's set theory the empty set is zero and the successor of each number is its unit set. | |
| From: report of Ernst Zermelo (works [1920]) by Simon Blackburn - Oxford Dictionary of Philosophy p.280 |
| 22180 | Multiple realisability is said to make reduction impossible [Okasha] |
| Full Idea: Philosophers have often invoked multiple realisability to explain why psychology cannot be reduced to physics or chemistry, but in principle the explanation works for any higher-level science. | |
| From: Samir Okasha (Philosophy of Science: Very Short Intro (2nd ed) [2016], 3) | |
| A reaction: He gives the example of a 'cell' in biology, which can be implemented in all sorts of ways. Presumably that can be reduced to many sorts of physics, but not just to one sort. The high level contains patterns that vanish at the low level. |
| 15990 | Every individual thing which exists has an essence, which is its internal constitution [Locke] |
| Full Idea: I take essences to be in everything that internal constitution or frame for the modification of substance, which God in his wisdom gives to every particular creature, when he gives it a being; and such essences I grant there are in all things that exist. | |
| From: John Locke (Letters to Edward Stillingfleet [1695], Letter 1), quoted by Simon Blackburn - Quasi-Realism no Fictionalism | |
| A reaction: This is the clearest statement I have found of Locke's commitment to essences, for all his doubts about whether we can know such things. Alexander says (ch.13) Locke was reacting against scholastic essence, as pertaining to species. |
| 15994 | If it is knowledge, it is certain; if it isn't certain, it isn't knowledge [Locke] |
| Full Idea: What reaches to knowledge, I think may be called certainty; and what comes short of certainty, I think cannot be knowledge. | |
| From: John Locke (Letters to Edward Stillingfleet [1695], Letter 2), quoted by Simon Blackburn - Quasi-Realism no Fictionalism | |
| A reaction: I much prefer that fallibilist approach offered by the pragmatists. Knowledge is well-supported belief which seems (and is agreed) to be true, but there is a small shadow of doubt hanging over all of it. |
| 22177 | Randomised Control Trials have a treatment and a control group, chosen at random [Okasha] |
| Full Idea: In the Randomised Controlled Trial for a new drug, patients are divided at random into a treatment group who receive the drug, and a control group who do not. Randomisation is important to eliminate confounding factors. | |
| From: Samir Okasha (Philosophy of Science: Very Short Intro (2nd ed) [2016], 2) | |
| A reaction: [compressed] Devised in the 1930s, and a major breakthrough in methodology for that kind of trial. Psychologists use the method all the time. Some theorists say it is the only reliable method. |
| 22172 | Not all sciences are experimental; astronomy relies on careful observation [Okasha] |
| Full Idea: Not all sciences are experimental - astronomers obviously cannot do experiments on the heavens, but have to content themselves with careful observation instead. | |
| From: Samir Okasha (Philosophy of Science: Very Short Intro (2nd ed) [2016], 1) | |
| A reaction: Biology too. Psychology tries hard to be experimental, but I doubt whether the main theories emerge from experiments. |
| 22174 | The discoverers of Neptune didn't change their theory because of an anomaly [Okasha] |
| Full Idea: Adams and Leverrier began with Newton's theory of gravity, which made an incorrect prediction about the orbit of Uranus. They explained away the conflicting observations by postulating a new planet, Neptune. | |
| From: Samir Okasha (Philosophy of Science: Very Short Intro (2nd ed) [2016], 1) | |
| A reaction: The falsificationists can say that the anomalous observation did not falsify the theory, because they didn't know quite what they were observing. It was not in fact an anomaly for Newtonian theory at all. |
| 22175 | Science mostly aims at confirming theories, rather than falsifying them [Okasha] |
| Full Idea: The goal of science is not solely to refute theories, but also to determine which theories are true (or probably true). When a scientist collects data …they are trying to show that their own theory is true. | |
| From: Samir Okasha (Philosophy of Science: Very Short Intro (2nd ed) [2016], 2) | |
| A reaction: This is the aim of 'accommodation' to a wide set of data, rather than prediction or refutation. |
| 22182 | Theories with unobservables are underdetermined by the evidence [Okasha] |
| Full Idea: According to anti-realists, scientific theories which posit unobservable entities are underdetermined by the empirical data - there will always be a number of competing theories which can account for the data equally well. | |
| From: Samir Okasha (Philosophy of Science: Very Short Intro (2nd ed) [2016], 4) | |
| A reaction: The fancy version is Putnam's model theoretic argument, explored by Tim Button. The reply, apparently, is that there are other criteria for theory choice, apart from the data. And we don't have to actually observe everything in a theory. |
| 22185 | Two things can't be incompatible if they are incommensurable [Okasha] |
| Full Idea: If two things are incommensurable they cannot be incompatible. | |
| From: Samir Okasha (Philosophy of Science: Very Short Intro (2nd ed) [2016], 5) | |
| A reaction: Kuhn had claimed that two rival theories are incompatible, which forces the paradigm shift. He can't stop the slide off into total relativism. The point is there cannot be a conflict if there cannot even be a comparison. |
| 22176 | Induction is inferences from examined to unexamined instances of a given kind [Okasha] |
| Full Idea: Some philosophers use 'inductive' to just mean not deductive, …but we reserve it for inferences from examined to unexamined instances of a given kind. | |
| From: Samir Okasha (Philosophy of Science: Very Short Intro (2nd ed) [2016], 2) | |
| A reaction: The instances must at least be comparable. Must you know the kind before you start? Surely you can examine a sequence of things, trying to decide whether or not they are of one kind? Is checking the uniformity of a kind induction? |
| 22178 | If the rules only concern changes of belief, and not the starting point, absurd views can look ratiional [Okasha] |
| Full Idea: If the only objective constraints concern how we should change our credences, but what our initial credences should be is entirely subjective, then individuals with very bizarre opinions about the world will count as perfectly rational. | |
| From: Samir Okasha (Philosophy of Science: Very Short Intro (2nd ed) [2016], 2) | |
| A reaction: The important rationality has to be the assessement of a diverse batch of evidence, for which there can never be any rules or mathematics. |
| 22173 | Galileo refuted the Aristotelian theory that heavier objects fall faster [Okasha] |
| Full Idea: Galileo's most enduring contribution lay in mechanics, where he refuted the Aristotelian theory that heavier bodies fall faster than lighter. | |
| From: Samir Okasha (Philosophy of Science: Very Short Intro (2nd ed) [2016], 2) | |
| A reaction: This must the first idea in the theory of mechanics, allowing mathematical treatment and accurate comparisons. |