25 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. |
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. |
17833 | The first-order ZF axiomatisation is highly non-categorical [Hallett,M] |
Full Idea: The first-order Sermelo-Fraenkel axiomatisation is highly non-categorical. | |
From: Michael Hallett (Introduction to Zermelo's 1930 paper [1996], p.1213) |
17834 | Non-categoricity reveals a sort of incompleteness, with sets existing that the axioms don't reveal [Hallett,M] |
Full Idea: The non-categoricity of the axioms which Zermelo demonstrates reveals an incompleteness of a sort, ....for this seems to show that there will always be a set (indeed, an unending sequence) that the basic axioms are incapable of revealing to be sets. | |
From: Michael Hallett (Introduction to Zermelo's 1930 paper [1996], p.1215) | |
A reaction: Hallett says the incompleteness concerning Zermelo was the (transfinitely) indefinite iterability of the power set operation (which is what drives the 'iterative conception' of sets). |
17837 | Zermelo allows ur-elements, to enable the widespread application of set-theory [Hallett,M] |
Full Idea: Unlike earlier writers (such as Fraenkel), Zermelo clearly allows that there might be ur-elements (that is, objects other than the empty set, which have no members). Indeed he sees in this the possibility of widespread application of set-theory. | |
From: Michael Hallett (Introduction to Zermelo's 1930 paper [1996], p.1217) |
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. |
17836 | The General Continuum Hypothesis and its negation are both consistent with ZF [Hallett,M] |
Full Idea: In 1938, Gödel showed that ZF plus the General Continuum Hypothesis is consistent if ZF is. Cohen showed that ZF and not-GCH is also consistent if ZF is, which finally shows that neither GCH nor ¬GCH can be proved from ZF itself. | |
From: Michael Hallett (Introduction to Zermelo's 1930 paper [1996], p.1217) |
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) | |
A reaction: A rather Platonic question! I presume that Heraclitus had a sense of beauty, and things regarded as 'sublime' are often tumultuous. |
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. |
18883 | Any equivalence relation among similar things allows the creation of an abstractum [Simons] |
Full Idea: Whenever we have an equivalence relation among things - such as similarity in a certain respect - we can abstract under the equivalence and consider the abstractum. | |
From: Peter Simons (Modes of Extension: comment on Fine [2008], p.19) | |
A reaction: This strikes me as dressing up old-fashioned psychological abstractionism in the respectable clothing of Fregean equivalences (such as 'directions'). We can actually do what Simons wants without the precision of partitioned equivalence classes. |
18884 | Abstraction is usually seen as producing universals and numbers, but it can do more [Simons] |
Full Idea: Abstraction as a cognitive tool has been associated predominantly with the metaphysics of universals and of mathematical objects such as numbers. But it is more widely applicable beyond this standard range. I commend its judicious use. | |
From: Peter Simons (Modes of Extension: comment on Fine [2008], p.21) | |
A reaction: Personally I think our view of the world is founded on three psychological principles: abstraction, idealisation and generalisation. You can try to give them rigour, as 'equivalence classes', or 'universal quantifications', if it makes you feel better. |
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. |
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) |