26 ideas
| 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. |
| 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) |
| 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. |
| 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. |
| 20653 | Six reduction levels: groups, lives, cells, molecules, atoms, particles [Putnam/Oppenheim, by Watson] |
| Full Idea: There are six 'reductive levels' in science: social groups, (multicellular) living things, cells, molecules, atoms, and elementary particles. | |
| From: report of H.Putnam/P.Oppenheim (Unity of Science as a Working Hypothesis [1958]) by Peter Watson - Convergence 10 'Intro' | |
| A reaction: I have the impression that fields are seen as more fundamental that elementary particles. What is the status of the 'laws' that are supposed to govern these things? What is the status of space and time within this picture? |
| 7127 | If men are good you should keep promises, but they aren't, so you needn't [Machiavelli] |
| Full Idea: If all men were good, promising-breaking would not be good, but because they are bad and do not keep their promises to you, you likewise do not have to keep yours to them. | |
| From: Niccolo Machiavelli (The Prince [1513], Ch.18) | |
| A reaction: A rather depressing proposal to get your promise-breaking in first, based on the pessimistic view that people cannot be improved. The subsequent history of ethics in Europe showed Machiavelli to be wrong. Gentlemen began to keep their word. |
| 6309 | The principle foundations of all states are good laws and good armies [Machiavelli] |
| Full Idea: The principle foundations of all states are good laws and good armies. | |
| From: Niccolo Machiavelli (The Prince [1513], Ch.11) | |
| A reaction: We may be wondering, since 1945, whether a good army is any longer essential, but it would be a foolish modern state which didn't at least form a strong alliance with a state which had a strong army. Fertile land is a huge benefit to a state. |
| 6305 | To retain a conquered state, wipe out the ruling family, and preserve everything else [Machiavelli] |
| Full Idea: If a ruler acquires a state and is determined to keep it, he observes two cautions: he wipes out the family of their long-established princes; and he does not change either their laws or their taxes; in a short time they will unite with his old princedom. | |
| From: Niccolo Machiavelli (The Prince [1513], Ch.3) | |
| A reaction: This nicely illustrates the firmness of purpose for which Machiavelli has become a byword. The question is whether Machiavelli had enough empirical evidence to support this induction. The British in India seem to have been successful without it. |
| 6306 | People are vengeful, so be generous to them, or destroy them [Machiavelli] |
| Full Idea: Men should be either treated generously or destroyed, because they take revenge for slight injuries. | |
| From: Niccolo Machiavelli (The Prince [1513], Ch.3) | |
| A reaction: This sounds like good advice, and works quite well in school teaching too. It seems like advice drawn from the growth of the Roman Empire, rather than from dealing with sophisticated and educated people. |
| 6308 | A sensible conqueror does all his harmful deeds immediately, because people soon forget [Machiavelli] |
| Full Idea: A prudent conqueror makes a list of all the harmful deeds he must do, and does them all at once, so that he need not repeat them every day, which then makes men feel secure, and gains their support by treating them well. | |
| From: Niccolo Machiavelli (The Prince [1513], Ch.8) | |
| A reaction: This might work for a new government in a democracy, or a new boss in a business. It sounds horribly true; dreadful deeds done a long time ago can be completely forgotten, as when reformed criminals become celebrities. |
| 6307 | A desire to conquer, and men who do it, are always praised, or not blamed [Machiavelli] |
| Full Idea: It is very natural and normal to wish to conquer, and when men do it who can, they always will be praised, or not blamed. | |
| From: Niccolo Machiavelli (The Prince [1513], Ch.3) | |
| A reaction: This view seems shocking to us, but it seems to me that this was a widely held view up until the time of Nietzsche, but came to a swift end with the invention of the machine gun in about 1885, followed by the heavy bomber and atomic bomb. |
| 19813 | All legislators invoke God in support of extraordinary laws, because their justification is not obvious [Machiavelli] |
| Full Idea: There has never been a single legislator who, in proposing extraordinary laws, did not have recourse to God, for otherwise they would not be accepted, since many benefits known to a prudent man do not have evident persuasive reasons. | |
| From: Niccolo Machiavelli (The Discourses [1520], 1.11), quoted by Jean-Jacques Rousseau - The Social Contract (tr Cress) II.7 n8 | |
| A reaction: It does seem to be an important role for God and state religion, to give support to decisions and laws which might not be intrinsically popular. |
| 7126 | Rulers should preserve the foundations of religion, to ensure good behaviour and unity [Machiavelli] |
| Full Idea: It is the duty of the rulers of a republic or a kingdom to preserve the foundations of the religion they hold; if they do this, it will be an easy thing for them to keep their state religious, and consequently good and united. | |
| From: Niccolo Machiavelli (The Discourses [1520], I.12) | |
| A reaction: This is the germ of Marx's view, that the sole role of religion is political, as a tool used by the ruling classes to keep the populace in their place. The same idea can be found in Critias (Idea 542). But what is wrong with some central moral guidance? |
| 7486 | Machiavelli emancipated politics from religion [Machiavelli, by Watson] |
| Full Idea: Machiavelli emancipated politics from religion. | |
| From: report of Niccolo Machiavelli (The Prince [1513]) by Peter Watson - Ideas Ch.24 | |
| A reaction: Interestingly, he seems to have done it by saying that ideals are irrelevant to politics, but gradually secular ideals crept back in (sometimes disastrously). A balance needs to be struck on idealism. |