26 ideas
| 17082 | Paradox: why do you analyse if you know it, and how do you analyse if you don't? [Ruben] |
| Full Idea: The alleged paradox of analysis asserts that if one knew what was involved in the concept, one would not need the analysis; if one did not know what was involved in the concept, no analysis could be forthcoming. | |
| From: David-Hillel Ruben (Explaining Explanation [1990], Ch 1) | |
| A reaction: This is the sort of problem that seemed to bug Plato a lot. You certainly can't analyse something if you don't understand it, but it seems obvious that you can illuminatingly analyse something of which you have a reasonable understanding. |
| 11223 | Definitions usually have a term, a 'definiendum' containing the term, and a defining 'definiens' [Gupta] |
| Full Idea: Many definitions have three elements: the term that is defined, an expression containing the defined term (the 'definiendum'), and another expression (the 'definiens') that is equated by the definition with this expression. | |
| From: Anil Gupta (Definitions [2008], 2) | |
| A reaction: He notes that the definiendum and the definiens are assumed to be in the 'same logical category', which is a right can of worms. |
| 11215 | Notable definitions have been of piety (Plato), God (Anselm), number (Frege), and truth (Tarski) [Gupta] |
| Full Idea: Notable examples of definitions in philosophy have been Plato's (e.g. of piety, in 'Euthyphro'), Anselm's definition of God, the Frege-Russell definition of number, and Tarski's definition of truth. | |
| From: Anil Gupta (Definitions [2008], Intro) | |
| A reaction: All of these are notable for the extensive metaphysical conclusions which then flow from what seems like a fairly neutral definition. We would expect that if we were defining essences, but not if we were just defining word usage. |
| 11227 | The 'revision theory' says that definitions are rules for improving output [Gupta] |
| Full Idea: The 'revision theory' of definitions says definitions impart a hypothetical character, giving a rule of revision rather than a rule of application. ...The output interpretation is better than the input one. | |
| From: Anil Gupta (Definitions [2008], 2.7) | |
| A reaction: Gupta mentions the question of whether such definitions can extend into the trans-finite. |
| 11225 | A definition needs to apply to the same object across possible worlds [Gupta] |
| Full Idea: In a modal logic in which names are non-vacuous and rigid, not only must existence and uniqueness in a definition be shown to hold necessarily, it must be shown that the definiens is satisfied by the same object across possible worlds. | |
| From: Anil Gupta (Definitions [2008], 2.4) |
| 11221 | A definition can be 'extensionally', 'intensionally' or 'sense' adequate [Gupta] |
| Full Idea: A definition is 'extensionally adequate' iff there are no actual counterexamples to it. It is 'intensionally adequate' iff there are no possible counterexamples to it. It is 'sense adequate' (or 'analytic') iff it endows the term with the right sense. | |
| From: Anil Gupta (Definitions [2008], 1.4) |
| 11224 | Traditional definitions are general identities, which are sentential and reductive [Gupta] |
| Full Idea: Traditional definitions are generalized identities (so definiendum and definiens can replace each other), in which the sentential is primary (for use in argument), and they involve reduction (and hence eliminability in a ground language). | |
| From: Anil Gupta (Definitions [2008], 2.2) |
| 11226 | Traditional definitions need: same category, mention of the term, and conservativeness and eliminability [Gupta] |
| Full Idea: A traditional definition requires that the definiendum contains the defined term, that definiendum and definiens are of the same logical category, and the definition is conservative (adding nothing new), and makes elimination possible. | |
| From: Anil Gupta (Definitions [2008], 2.4) |
| 11217 | Chemists aim at real definition of things; lexicographers aim at nominal definition of usage [Gupta] |
| Full Idea: The chemist aims at real definition, whereas the lexicographer aims at nominal definition. ...Perhaps real definitions investigate the thing denoted, and nominal definitions investigate meaning and use. | |
| From: Anil Gupta (Definitions [2008], 1.1) | |
| A reaction: Very helpful. I really think we should talk much more about the neglected chemists when we discuss science. Theirs is the single most successful branch of science, the paradigm case of what the whole enterprise aims at. |
| 11216 | If definitions aim at different ideals, then defining essence is not a unitary activity [Gupta] |
| Full Idea: Some definitions aim at precision, others at fairness, or at accuracy, or at clarity, or at fecundity. But if definitions 'give the essence of things' (the Aristotelian formula), then it may not be a unitary kind of activity. | |
| From: Anil Gupta (Definitions [2008], 1) | |
| A reaction: We don't have to accept this conclusion so quickly. Human interests may shift the emphasis, but there may be a single ideal definition of which these various examples are mere parts. |
| 11218 | Stipulative definition assigns meaning to a term, ignoring prior meanings [Gupta] |
| Full Idea: Stipulative definition imparts a meaning to the defined term, and involves no commitment that the assigned meaning agrees with prior uses (if any) of the term | |
| From: Anil Gupta (Definitions [2008], 1.3) | |
| A reaction: A nice question is how far one can go in stretching received usage. If I define 'democracy' as 'everyone is involved in decisions', that is sort of right, but pushing the boundaries (children, criminals etc). |
| 11220 | Ostensive definitions look simple, but are complex and barely explicable [Gupta] |
| Full Idea: Ostensive definitions look simple (say 'this stick is one meter long', while showing a stick), but they are effective only because a complex linguistic and conceptual capacity is operative in the background, of which it is hard to give an account. | |
| From: Anil Gupta (Definitions [2008], 1.2) | |
| A reaction: The full horror of the situation is brought out in Quine's 'gavagai' example (Idea 6312) |
| 14965 | Truth rests on Elimination ('A' is true → A) and Introduction (A → 'A' is true) [Gupta] |
| Full Idea: The basic principles governing truth are Truth Elimination (sentence A follows from ''A' is true') and the converse Truth Introduction (''A' is true' follows from A), which combine into Tarski's T-schema - 'A' is true if and only if A. | |
| From: Anil Gupta (Truth [2001], 5.1) | |
| A reaction: Introduction and Elimination rules are the basic components of natural deduction systems, so 'true' now works in the same way as 'and', 'or' etc. This is the logician's route into truth. |
| 14968 | A weakened classical language can contain its own truth predicate [Gupta] |
| Full Idea: If a classical language is expressively weakened - for example, by dispensing with negation - then it can contain its own truth predicate. | |
| From: Anil Gupta (Truth [2001], 5.2) | |
| A reaction: Thus the Tarskian requirement to move to a metalanguage for truth is only a requirement of a reasonably strong language. Gupta uses this to criticise theories that dispense with the metalanguage. |
| 11222 | The ordered pair <x,y> is defined as the set {{x},{x,y}}, capturing function, not meaning [Gupta] |
| Full Idea: The ordered pair <x,y> is defined as the set {{x},{x,y}}. This does captures its essential uses. Pairs <x,y> <u,v> are identical iff x=u and y=v, and the definition satisfies this. Function matters here, not meaning. | |
| From: Anil Gupta (Definitions [2008], 1.5) | |
| A reaction: This is offered as an example of Carnap's 'explications', rather than pure definitions. Quine extols it as a philosophical paradigm (1960:§53). |
| 14964 | The Liar reappears, even if one insists on propositions instead of sentences [Gupta] |
| Full Idea: There is the idea that the Liar paradox is solved simply by noting that truth is a property of propositions (not of sentences), and the Liar sentence does not express a proposition. But we then say 'I am not now expressing a true proposition'! | |
| From: Anil Gupta (Truth [2001], 5.1) | |
| A reaction: Disappointed to learn this, since I think focusing on propositions (which are unambiguous) rather than sentences solves a huge number of philosophical problems. |
| 14969 | Strengthened Liar: either this sentence is neither-true-nor-false, or it is not true [Gupta] |
| Full Idea: An example of the Strengthened Liar is the following statement SL: 'Either SL is neither-true-nor-false or it is not true'. This raises a serious problem for any theory that assesses the paradoxes to be neither true nor false. | |
| From: Anil Gupta (Truth [2001], 5.4.2) | |
| A reaction: If the sentence is either true or false it reduces to the ordinary Liar. If it is neither true nor false, then it is true. |
| 16643 | Accidents always remain suited to a subject [Bonaventura] |
| Full Idea: An accident's aptitudinal relationship to a subject is essential, and this is never taken away from accidents….for it is true to say that they are suited to a subject. | |
| From: Bonaventura (Commentary on Sentences [1252], IV.12.1.1.1c) | |
| A reaction: This is the compromise view that allows accidents to be separated, for Transubstantiation, while acknowledging that we identify them with their subjects. |
| 16696 | Successive things reduce to permanent things [Bonaventura] |
| Full Idea: Everything successive reduces to something permanent. | |
| From: Bonaventura (Commentary on Sentences [1252], II.2.1.1.3 ad 5), quoted by Robert Pasnau - Metaphysical Themes 1274-1671 18.2 | |
| A reaction: Avicenna first took successive entities seriously, but Bonaventure and Aquinas seem to have rejected them, or given reductive accounts of them. It resembles modern actualists versus modal realists. |
| 17087 | The 'symmetry thesis' says explanation and prediction only differ pragmatically [Ruben] |
| Full Idea: The 'symmetry thesis' holds that there is only a pragmatic, or epistemic, but no logical, difference between explaining and predicting. …The only difference is in what the producer of the deduction knows just before the deduction is produced. | |
| From: David-Hillel Ruben (Explaining Explanation [1990], Ch 4) | |
| A reaction: He cites Mill has holding this view. It seems elementary to me that I can explain something but not predict it, or predict it but not explain it. The latter case is just Humean habitual induction. |
| 17081 | Usually explanations just involve giving information, with no reference to the act of explanation [Ruben] |
| Full Idea: Plato, Aristotle, Mill and Hempel believed that an explanatory product can be characterized solely in terms of the kind of information it conveys, no reference to the act of explaining being required. | |
| From: David-Hillel Ruben (Explaining Explanation [1990], Ch 1) | |
| A reaction: Achinstein says it's about acts, because the same information could be an explanation, or a critique, or some other act. Ruben disagrees, and so do I. |
| 17092 | An explanation needs the world to have an appropriate structure [Ruben] |
| Full Idea: Objects or events in the world must really stand in some appropriate 'structural' relation before explanation is possible. | |
| From: David-Hillel Ruben (Explaining Explanation [1990], Ch 7) | |
| A reaction: An important point. These days people talk of 'dependence relations'. Some sort of structure to reality (mainly imposed by the direction of time and causation, I would have thought) is a prerequisite of finding a direction to explanation. |
| 17090 | Most explanations are just sentences, not arguments [Ruben] |
| Full Idea: Typically, full explanations are not arguments, but singular sentences, or conjunctions thereof. | |
| From: David-Hillel Ruben (Explaining Explanation [1990], Ch 6) | |
| A reaction: This is mainly objecting to the claim that explanations are deductions from laws and facts. I agree with Ruben. Explanations are just information, I think. Of course, Aristotle's demonstrations are arguments. |
| 17094 | The causal theory of explanation neglects determinations which are not causal [Ruben] |
| Full Idea: The fault of the causal theory of explanation was to overlook the fact that there are more ways of making something what it is or being responsible for it than by causing it. …Causation is a particular type of determinative relation. | |
| From: David-Hillel Ruben (Explaining Explanation [1990], Ch 7) | |
| A reaction: The only thing I can think of is that certain abstract facts are 'determined' by other abtract facts, without being 'caused' by them. A useful word. |
| 17088 | Reducing one science to another is often said to be the perfect explanation [Ruben] |
| Full Idea: The reduction of one science to another has often been taken as paradigmatic of explanation. | |
| From: David-Hillel Ruben (Explaining Explanation [1990], Ch 5) | |
| A reaction: It seems fairly obvious that the total reduction of chemistry to physics would involve the elimination of all the current concepts of chemistry. Could this possibly enhance our understanding of chemistry? I would have thought not. |
| 17089 | Facts explain facts, but only if they are conceptualised or named appropriately [Ruben] |
| Full Idea: Facts explain facts only when the features and the individuals the facts are about are appropriately conceptualized or named. | |
| From: David-Hillel Ruben (Explaining Explanation [1990], Ch 5) | |
| A reaction: He has a nice example that 'Cicero's speeches stop in 43 BCE' isn't explained by 'Tully died then', if you don't know that Cicero was Tully. Ruben is not defending pragmatic explanation, but to this extent he must be right. |