27 ideas
| 5896 | Speak the truth, for this alone deifies man [Pythagoras, by Porphyry] |
| Full Idea: Pythagoras advised above all things to speak the truth, for this alone deifies man. | |
| From: report of Pythagoras (reports [c.530 BCE]) by Porphyry - Life of Pythagoras §41 | |
| A reaction: Idea 4421 (of Nietzsche) stands in contrast to this. I am not quite sure why speaking the truth has such a high value. I am inclined to a minimalist view, which is just that philosophy is an attempt to speak the truth, as fishermen try to catch fish. |
| 3051 | Pythagoras discovered the numerical relation of sounds on a string [Pythagoras, by Diog. Laertius] |
| Full Idea: Pythagoras discovered the numerical relation of sounds on a string. | |
| From: report of Pythagoras (reports [c.530 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 08.1.11 |
| 16985 | Possible worlds allowed the application of set-theoretic models to modal logic [Kripke] |
| Full Idea: The main and the original motivation for the 'possible worlds analysis' - and the way it clarified modal logic - was that it enabled modal logic to be treated by the same set theoretic techniques of model theory used successfully in extensional logic. | |
| From: Saul A. Kripke (Naming and Necessity preface [1980], p.19 n18) | |
| A reaction: So they should be ascribed the same value that we attribute to classical model theory, whatever that is. |
| 16982 | A man has two names if the historical chains are different - even if they are the same! [Kripke] |
| Full Idea: Two totally distinct 'historical chains' that be sheer accident assign the same name to the same man should probably count as creating distinct names despite the identity of the referents. | |
| From: Saul A. Kripke (Naming and Necessity preface [1980], p.08 n9) | |
| A reaction: A nice puzzle for his own theory. 'What's you name?' 'Alice, and Alice!' |
| 7485 | For Pythagoreans 'one' is not a number, but the foundation of numbers [Pythagoras, by Watson] |
| Full Idea: For Pythagoreans, one, 1, is not a true number but the 'essence' of number, out of which the number system emerges. | |
| From: report of Pythagoras (reports [c.530 BCE], Ch.8) by Peter Watson - Ideas Ch.8 | |
| A reaction: I think this is right! Counting and numbers only arise once the concept of individuality and identity have arisen. Counting to one is no more than observing the law of identity. 'Two' is the big adventure. |
| 1635 | Mathematics reduces to set theory (which is a bit vague and unobvious), but not to logic proper [Quine] |
| Full Idea: Mathematics reduces only to set theory, and not to logic proper… but set theory cannot claim the same firmness and obviousness as logic. | |
| From: Willard Quine (Epistemology Naturalized [1968], p.69-70) |
| 16981 | With the necessity of self-identity plus Leibniz's Law, identity has to be an 'internal' relation [Kripke] |
| Full Idea: It is clear from (x)□(x=x) and Leibniz's Law that identity is an 'internal' relation: (x)(y)(x=y ⊃ □x=y). What pairs (w,y) could be counterexamples? Not pairs of distinct objects, …nor an object and itself. | |
| From: Saul A. Kripke (Naming and Necessity preface [1980], p.03) | |
| A reaction: I take 'internal' to mean that the necessity of identity is intrinsic to the item(s), and not imposed by some other force. |
| 4942 | The indiscernibility of identicals is as self-evident as the law of contradiction [Kripke] |
| Full Idea: It seems to me that the Leibnizian principle of the indiscernibility of identicals (not to be confused with the identity of indiscernibles) is as self-evident as the law of contradiction. | |
| From: Saul A. Kripke (Naming and Necessity preface [1980], p.03) | |
| A reaction: This seems obviously correct, as it says no more than that a thing has whatever properties it has. If a difference is discerned, either you have made a mistake, or it isn't identical. |
| 16984 | I don't think possible worlds reductively reveal the natures of modal operators etc. [Kripke] |
| Full Idea: I do not think of 'possible worlds' as providing a reductive analysis in any philosophically significant sense, that is, as uncovering the ultimate nature, from either an epistemological or a metaphysical view, of modal operators, propositions etc. | |
| From: Saul A. Kripke (Naming and Necessity preface [1980], p.19 n18) | |
| A reaction: I think this remark opens the door for Kit Fine's approach, of showing what modality is by specifying its sources. Possible worlds model the behaviour of modal inferences. |
| 9385 | The very act of designating of an object with properties gives knowledge of a contingent truth [Kripke] |
| Full Idea: If a speaker introduced a designator into a language by a ceremony, then in virtue of his very linguistic act, he would be in a position to say 'I know that Fa', but nevertheless 'Fa' would be a contingent truth (provided F is not an essential property). | |
| From: Saul A. Kripke (Naming and Necessity preface [1980], p.14) | |
| A reaction: If someone else does the designation, I seem to have contingent knowledge that the ceremony has taken place. You needn't experience the object, but you must experience the ceremony, even if you perform it. |
| 4943 | Instead of talking about possible worlds, we can always say "It is possible that.." [Kripke] |
| Full Idea: We should remind ourselves the 'possible worlds' terminology can always be replaced by modal talk, such as "It is possible that…" | |
| From: Saul A. Kripke (Naming and Necessity preface [1980], p.15) | |
| A reaction: Coming from an originator of the possible worlds idea, this is a useful reminder that we don't have to get too excited about the ontological commitments involved. It may be just a 'way to talk', and hence a tool, rather than a truth about reality. |
| 16983 | Probability with dice uses possible worlds, abstractions which fictionally simplify things [Kripke] |
| Full Idea: In studying probabilities with dice, we are introduced at a tender age to a set of 36 (miniature) possible worlds, if we (fictively) ignore everything except the two dice. …The possibilities are abstract states of the dice, not physical entities. | |
| From: Saul A. Kripke (Naming and Necessity preface [1980], p.16) | |
| A reaction: Interesting for the introduction by the great man of the words 'fictional' and 'abstract' into the discussion. He says elsewhere that he takes worlds to be less than real, but more than mere technical devices. |
| 7627 | You can't reduce epistemology to psychology, because that presupposes epistemology [Maund on Quine] |
| Full Idea: There is something seriously misguided about Quine's project of reducing epistemology to psychology, since psychology, like any of the natural sciences, presupposes an epistemology. | |
| From: comment on Willard Quine (Epistemology Naturalized [1968]) by Barry Maund - Perception Ch.1 | |
| A reaction: I wonder if epistemology presupposes psychology? Belief, for example, is a category of folk psychology, which could be challenged. There is a quiet battle going on between philosophy and science. |
| 8871 | We should abandon a search for justification or foundations, and focus on how knowledge is acquired [Quine, by Davidson] |
| Full Idea: Quine is suggesting that philosophy should abandon the attempt to provide a foundation for knowledge, or otherwise justify it, and should instead give an account of how knowledge is acquired. | |
| From: report of Willard Quine (Epistemology Naturalized [1968]) by Donald Davidson - Epistemology Externalized p.193 | |
| A reaction: If you are going to explain how 'knowledge' is acquired, you'd better know what knowledge is. My suspicion is that Quine would be quite happy (in the pragmatist tradition) to just focus on belief, and forget about knowledge entirely. |
| 8826 | If we abandon justification and normativity in epistemology, we must also abandon knowledge [Kim on Quine] |
| Full Idea: Quine asks us to set aside the entire framework of justification-centered epistemology, ..and repudiate normativity. ..But then knowledge itself drops out of epistemology, for our concept of knowledge is inseparably tied to that of justification. | |
| From: comment on Willard Quine (Epistemology Naturalized [1968]) by Jaegwon Kim - What is 'naturalized epistemology'? p.305 | |
| A reaction: Presumably this would not bother Quine, who wants to hand so-called 'epistemology' over to the psychologists. A psychological account of belief seems plausible. Presumably false beliefs could only be pragmatically characterised. |
| 8827 | Without normativity, naturalized epistemology isn't even about beliefs [Kim on Quine] |
| Full Idea: If normativity is wholly excluded from naturalized epistemology it cannot even be thought of as being about beliefs. | |
| From: comment on Willard Quine (Epistemology Naturalized [1968]) by Jaegwon Kim - What is 'naturalized epistemology'? p.306 | |
| A reaction: And if it doesn't refer to beliefs, it certainly doesn't refer to knowledge. One might try to subsume normativity under evolutionary pragmatic 'drives', or something. Quine's project would then become wildly speculative, and hence boring. |
| 8899 | Epistemology is a part of psychology, studying how our theories relate to our evidence [Quine] |
| Full Idea: Epistemology falls into place as a chapter of psychology, and hence of natural science. ..We study meagre input and torrential output, to see how evidence relates to theory, and in what ways one's theory of nature transcends any available evidence. | |
| From: Willard Quine (Epistemology Naturalized [1968], p.83) | |
| A reaction: It depends what you are interested in. If you just want to know what makes humans tick, then Quine is your man, but if you want to know things in general, and want to know how to get it right, then the normative side of epistemology is unavoidable. |
| 8898 | Inculcations of meanings of words rests ultimately on sensory evidence [Quine] |
| Full Idea: All inculcation of meanings of words must rest ultimately on sensory evidence. | |
| From: Willard Quine (Epistemology Naturalized [1968], p.75) | |
| A reaction: This betrays Quine's behaviourist tendencies, and rules out introspection, definitions and inferences. Quine's conclusion is fairly total scepticism about meaning, but that is not surprising, given his external and meaningless starting point. |
| 8900 | In observation sentences, we could substitute community acceptance for analyticity [Quine] |
| Full Idea: Perhaps the controversial notion of analyticity can be dispensed with, in our definition of observation sentences, in favour of the straightforward attitude of community-wide acceptance. | |
| From: Willard Quine (Epistemology Naturalized [1968], p.86) | |
| A reaction: That might be a reasonable account of 'bachelors'. If the whole community accepts 'God exists', does that make it analytic? If a whole (small!) community claims to actually observe a ghost or a flying saucer, is that then analytic? |
| 3053 | Pythagoras taught that virtue is harmony, and health, and universal good, and God [Pythagoras, by Diog. Laertius] |
| Full Idea: Pythagoras taught that virtue is harmony, and health, and universal good, and God. | |
| From: report of Pythagoras (reports [c.530 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 08.1.19 | |
| A reaction: I like the link with health, because I consider that a bridge over the supposed fact-value gap. Very Pythagorean to think that virtue is harmony. Plato liked that thought. |
| 5244 | For Pythagoreans, justice is simply treating all people the same [Pythagoras, by Aristotle] |
| Full Idea: Some even think that what is just is simple reciprocity, as the Pythagoreans maintained, because they defined justice simply as having done to one what one has done to another. | |
| From: report of Pythagoras (reports [c.530 BCE], 28) by Aristotle - Nicomachean Ethics 1132b22 | |
| A reaction: One wonders what Pythagoreans made of slavery. Aristotle argues that officials, for example, have superior rights. The Pythagorean idea makes fairness the central aspect of justice, and that must at least be partly right. |
| 375 | When musical harmony and rhythm were discovered, similar features were seen in bodily movement [Pythagoras, by Plato] |
| Full Idea: When our predecessors discovered musical scales, they also discovered similar features in bodily movement, which should also be measured numerically, and called 'tempos' and 'measures'. | |
| From: report of Pythagoras (reports [c.530 BCE]) by Plato - Philebus 17d |
| 638 | Pythagoreans define timeliness, justice and marriage in terms of numbers [Pythagoras, by Aristotle] |
| Full Idea: The Pythagoreans offered definitions of a limited range of things on the basis of numbers; examples are timeliness, justice and marriage. | |
| From: report of Pythagoras (reports [c.530 BCE]) by Aristotle - Metaphysics 1078b |
| 553 | Pythagoreans think mathematical principles are the principles of all of nature [Pythagoras, by Aristotle] |
| Full Idea: The Pythagoreans thought that the principles of mathematical entities were the principles of all entities. | |
| From: report of Pythagoras (reports [c.530 BCE]) by Aristotle - Metaphysics 985b |
| 554 | Pythagoreans say things imitate numbers, but Plato says things participate in numbers [Pythagoras, by Aristotle] |
| Full Idea: Pythagoreans said that entities existed by imitation of the numbers, whereas Plato said that it was by participation. | |
| From: report of Pythagoras (reports [c.530 BCE]) by Aristotle - Metaphysics 987b |
| 644 | For Pythagoreans the entire universe is made of numbers [Pythagoras, by Aristotle] |
| Full Idea: For Pythagoreans the entire universe is constructed of numbers. | |
| From: report of Pythagoras (reports [c.530 BCE]) by Aristotle - Metaphysics 1080b |
| 7467 | The modern idea of an immortal soul was largely created by Pythagoras [Pythagoras, by Watson] |
| Full Idea: The modern concept of the immortal soul is a Greek idea, which owes much to Pythagoras. | |
| From: report of Pythagoras (reports [c.530 BCE]) by Peter Watson - Ideas Ch.5 | |
| A reaction: You can see why it caught on - it is a very appealing idea. Watson connects the 'modern' view with the ideas of heaven and hell. Obviously the idea of an afterlife goes a long way back (judging from the contents of ancient graves). |