36 ideas
13786 | Wisdom is called 'beautiful', because it performs fine works [Plato] |
Full Idea: Wisdom [phronesis] is correctly given the name 'kalon' [beautiful], since it performs the works that we say are beautiful and welcome as such. | |
From: Plato (Cratylus [c.377 BCE], 416d) | |
A reaction: 'Phronesis' in Aristotle is more like prudence, or common sense, rather than wisdom ['sophia']. 'Kalon' also means fine or noble. This translation seems fair enough, though. |
13780 | Good people are no different from wise ones [Plato] |
Full Idea: Socrates: Are good people any different from wise ones? No, they aren't. | |
From: Plato (Cratylus [c.377 BCE], 398b) | |
A reaction: This is Socrates's 'intellectualism', his view that being good is entirely a matter of reason and knowledge, and not a matter of habit or emotion. Do we still accept the traditional assumption that wise people are thereby morally good? |
13778 | A dialectician is someone who knows how to ask and to answer questions [Plato] |
Full Idea: What would you call someone who knows how to ask and answer questions? Wouldn't you call him a dialectician? | |
From: Plato (Cratylus [c.377 BCE], 390c) | |
A reaction: Asking good questions and giving good answers sound like two very different skills. I presume dialectic is the process of arriving at answers by means of asking the right questions. |
15647 | Truth definitions don't produce a good theory, because they go beyond your current language [Halbach] |
Full Idea: It is far from clear that a definition of truth can lead to a philosophically satisfactory theory of truth. Tarski's theorem on the undefinability of the truth predicate needs resources beyond those of the language for which it is being defined. | |
From: Volker Halbach (Axiomatic Theories of Truth (2005 ver) [2005], 1) | |
A reaction: The idea is that you need a 'metalanguage' for the definition. If I say 'p' is a true sentence in language 'L', I am not making that observation from within language L. The dream is a theory confined to the object language. |
13776 | Truths say of what is that it is, falsehoods say of what is that it is not [Plato] |
Full Idea: Those statements that say of the things that are that they are, are true, while those that say of the things that are that they are not, are false. | |
From: Plato (Cratylus [c.377 BCE], 385b) | |
A reaction: It was quite a shock to discover this, because the famous Aristotle definition (Idea 586) is always quoted, and no modern writers seem to have any awareness of the Plato remark. Classical scholarship is very poor in analytic philosophy. |
15649 | In semantic theories of truth, the predicate is in an object-language, and the definition in a metalanguage [Halbach] |
Full Idea: In semantic theories of truth (Tarski or Kripke), a truth predicate is defined for an object-language. This definition is carried out in a metalanguage, which is typically taken to include set theory or another strong theory or expressive language. | |
From: Volker Halbach (Axiomatic Theories of Truth (2005 ver) [2005], 1) | |
A reaction: Presumably the metalanguage includes set theory because that connects it with mathematics, and enables it to be formally rigorous. Tarski showed, in his undefinability theorem, that the meta-language must have increased resources. |
15655 | Should axiomatic truth be 'conservative' - not proving anything apart from implications of the axioms? [Halbach] |
Full Idea: If truth is not explanatory, truth axioms should not allow proof of new theorems not involving the truth predicate. It is hence said that axiomatic truth should be 'conservative' - not implying further sentences beyond what the axioms can prove. | |
From: Volker Halbach (Axiomatic Theories of Truth (2005 ver) [2005], 1.3) | |
A reaction: [compressed] |
15654 | If truth is defined it can be eliminated, whereas axiomatic truth has various commitments [Halbach] |
Full Idea: If truth can be explicitly defined, it can be eliminated, whereas an axiomatized notion of truth may bring all kinds of commitments. | |
From: Volker Halbach (Axiomatic Theories of Truth (2005 ver) [2005], 1.3) | |
A reaction: The general principle that anything which can be defined can be eliminated (in an abstract theory, presumably, not in nature!) raises interesting questions about how many true theories there are which are all equivalent to one another. |
15650 | Axiomatic theories of truth need a weak logical framework, and not a strong metatheory [Halbach] |
Full Idea: Axiomatic theories of truth can be presented within very weak logical frameworks which require very few resources, and avoid the need for a strong metalanguage and metatheory. | |
From: Volker Halbach (Axiomatic Theories of Truth (2005 ver) [2005], 1) |
15648 | Instead of a truth definition, add a primitive truth predicate, and axioms for how it works [Halbach] |
Full Idea: The axiomatic approach does not presuppose that truth can be defined. Instead, a formal language is expanded by a new primitive predicate of truth, and axioms for that predicate are then laid down. | |
From: Volker Halbach (Axiomatic Theories of Truth (2005 ver) [2005], 1) | |
A reaction: Idea 15647 explains why Halbach thinks the definition route is no good. |
15656 | Deflationists say truth merely serves to express infinite conjunctions [Halbach] |
Full Idea: According to many deflationists, truth serves merely the purpose of expressing infinite conjunctions. | |
From: Volker Halbach (Axiomatic Theories of Truth (2005 ver) [2005], 1.3) | |
A reaction: That is, it asserts sentences that are too numerous to express individually. It also seems, on a deflationist view, to serve for anaphoric reference to sentences, such as 'what she just said is true'. |
15657 | To prove the consistency of set theory, we must go beyond set theory [Halbach] |
Full Idea: The consistency of set theory cannot be established without assumptions transcending set theory. | |
From: Volker Halbach (Axiomatic Theories of Truth (2005 ver) [2005], 2.1) |
15652 | We can use truth instead of ontologically loaded second-order comprehension assumptions about properties [Halbach] |
Full Idea: The reduction of 2nd-order theories (of properties or sets) to axiomatic theories of truth may be conceived as a form of reductive nominalism, replacing existence assumptions (for comprehension axioms) by ontologically innocent truth assumptions. | |
From: Volker Halbach (Axiomatic Theories of Truth (2005 ver) [2005], 1.1) | |
A reaction: I like this very much, as weeding properties out of logic (without weeding them out of the world). So-called properties in logic are too abundant, so there is a misfit with their role in science. |
15651 | Instead of saying x has a property, we can say a formula is true of x - as long as we have 'true' [Halbach] |
Full Idea: Quantification over (certain) properties can be mimicked in a language with a truth predicate by quantifying over formulas. Instead of saying that Tom has the property of being a poor philosopher, we can say 'x is a poor philosopher' is true of Tom. | |
From: Volker Halbach (Axiomatic Theories of Truth (2005 ver) [2005], 1.1) | |
A reaction: I love this, and think it is very important. He talks of 'mimicking' properties, but I see it as philosophers mistakenly attributing properties, when actually what they were doing is asserting truths involving certain predicates. |
13777 | A name is a sort of tool [Plato] |
Full Idea: A name is a sort of tool. | |
From: Plato (Cratylus [c.377 BCE], 388a) | |
A reaction: Idea 13775 gives a background for this metaphor, from earlier in the text. Wittgenstein has a famous toolkit metaphor for language. The whole of this text, 'Cratylus', is about names. |
13790 | A name-giver might misname something, then force other names to conform to it [Plato] |
Full Idea: The name-giver might have made a mistake at the beginning and then forced the other names to be consistent with it. | |
From: Plato (Cratylus [c.377 BCE], 436c) | |
A reaction: Lovely. This is Gareth Evans's 'Madagascar' example. See Idea 9041. |
13791 | Things must be known before they are named, so it can't be the names that give us knowledge [Plato] |
Full Idea: If things cannot be learned except from their names, how can we possibly claim that the name-givers or rule-setters have knowledge before any names had been given for them to know? | |
From: Plato (Cratylus [c.377 BCE], 438b) | |
A reaction: Running through this is a hostility to philosophy of language, so I find it very congenial. We are animals who relate to the world before language takes a grip. We have full-blown knowledge of things, with no intervention of words. |
13789 | Anyone who knows a thing's name also knows the thing [Plato] |
Full Idea: The simple truth is that anyone who knows a thing's name also knows the thing. | |
From: Plato (Cratylus [c.377 BCE], 435d) | |
A reaction: A nice slogan, but it seems to be blatantly false. The best example is Gareth Evans's of joining in a conversation about a person ('Louis'?), and only gradually tuning in to the person to which the name refers. |
2063 | How can beauty have identity if it changes? [Plato] |
Full Idea: If beauty never stays the same, how can it be something? | |
From: Plato (Cratylus [c.377 BCE], 439e) |
13775 | We only succeed in cutting if we use appropriate tools, not if we approach it randomly [Plato] |
Full Idea: If we undertake to cut something and make the cut in whatever way we choose and with whatever tool we choose, we will not succeed. If we cut according to the nature of cutting and being cut, and with the natural tool, we'll succeed and cut correctly. | |
From: Plato (Cratylus [c.377 BCE], 387a) | |
A reaction: I take this passage to be the creed for realists about the physical world - a commitment not merely to the existence of an external world, but to the existence of facts about it, which we may or may not be able to discover. |
13787 | Doesn't each thing have an essence, just as it has other qualities? [Plato] |
Full Idea: Don't you think that just as each thing has a colour or some of those other qualities we mentioned, it also has a being or essence? | |
From: Plato (Cratylus [c.377 BCE], 423e) | |
A reaction: The Greek here seems to be 'ousia', which I increasingly think should be translated as 'distinct identity', rather than as 'existence' or as 'essence'. Maybe the philosophical term 'haecceity' captures it best. |
13774 | Things don't have every attribute, and essence isn't private, so each thing has an essence [Plato] |
Full Idea: If Euthydemus is wrong that everything always has every attribute simultaneously, or that being or essence is private for each person, then it is clear that things have some fixed being or essence of their own. | |
From: Plato (Cratylus [c.377 BCE], 386d) | |
A reaction: I'm not sure what 'being or essence' translates. If it translates 'ousia' then I wouldn't make too much of this remark from an essentialist point of view. |
13772 | Is the being or essence of each thing private to each person? [Plato] |
Full Idea: Is the being or essence of each of the things that are something private to each person, as Protagoras tells us? | |
From: Plato (Cratylus [c.377 BCE], 385e) | |
A reaction: This kind of drastic personal relativism about essences doesn't sound very plausible, but the idea that essences are private to each culture, or to each language, must certainly be taken seriously. |
13788 | If we made a perfect duplicate of Cratylus, there would be two Cratyluses [Plato] |
Full Idea: Soc: Suppose we made a duplicate of everything you have and put it beside you; would there then be two Cratyluses, or Cratylus and an image of Cratylus? Crat: It seems to me, Socrates, that there would be two Cratyluses. | |
From: Plato (Cratylus [c.377 BCE], 432c) | |
A reaction: Don't think that science fiction examples are a modern development in philosophy. Plato has just invented the Startrek transporter. The two Cratyluses are the two spheres in Max Black's famous example. |
13792 | There can't be any knowledge if things are constantly changing [Plato] |
Full Idea: It isn't even reasonable to say that there is such a thing as knowledge, Cratylus, if all things are passing on and none remain. | |
From: Plato (Cratylus [c.377 BCE], 440a) | |
A reaction: This encapsulates Plato's horror at Heraclitus scepticism about the stable identity of things. It leads to the essentialism of Aristotle and Leibniz, who fear that there is no knowledge if we can't pin down individual identities. Know processes? |
13781 | Soul causes the body to live, and gives it power to breathe and to be revitalized [Plato] |
Full Idea: Those who named the soul thought that when the soul is present in the body, it causes it to live and gives it the power to breathe the air and be revitalized [anapsuchon]. | |
From: Plato (Cratylus [c.377 BCE], 399d) | |
A reaction: I quote this to emphasis that Greek psuché is very different from the consciousness which is largely discussed in modern philosophy of mind. I find it helpful to make a real effort to grasp the Greek concept. The feeling of life within you. |
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. |
13785 | 'Arete' signifies lack of complexity and a free-flowing soul [Plato] |
Full Idea: 'Areté' signifies lack of perplexity [euporia, ease of movement], and that the flow of a good soul is unimpeded. | |
From: Plato (Cratylus [c.377 BCE], 415d) | |
A reaction: Some highly dubious etymology going on here, and throughout 'Cratylus', but it gives a nice feeling for the way Socrates and Plato saw virtue. |
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. |
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. |
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. |
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. |
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. |
13779 | The natural offspring of a lion is called a 'lion' (but what about the offspring of a king?) [Plato] |
Full Idea: It seems to me that it is right to call a lion's offspring a 'lion' and a horse's offspring a 'horse' (I'm talking about natural offspring, not some monster). ...but by the same argument any offspring of a king should be called a 'king'. | |
From: Plato (Cratylus [c.377 BCE], 393b) | |
A reaction: The standard modern difficulty is whether all descendants of dinosaurs are still called 'dinosaur', which they are not. |
13783 | Even the gods love play [Plato] |
Full Idea: Even the gods love play. | |
From: Plato (Cratylus [c.377 BCE], 406c) |