105 ideas
| 13310 | Wisdom does not lie in books, and unread people can also become wise [Seneca] |
| Full Idea: What grounds could I possibly have for supposing that a person who has no acquaintance with books will never be a wise man? For wisdom does not lie in books. | |
| From: Seneca the Younger (Letters from a Stoic [c.60], 088) | |
| A reaction: A useful warning to the likes of me, who may have retreated from the hurly-burly of the agora (see Callicles in Plato's 'Gorgias'), under the illusion that detachment is needed for wisdom. Maybe involvement is needed for wisdom. |
| 13295 | Wise people escape necessity by willing it [Seneca] |
| Full Idea: There is nothing a wise man does reluctantly; he escapes necessity because he wills what necessity is going to force on him. | |
| From: Seneca the Younger (Letters from a Stoic [c.60], 054) | |
| A reaction: He is discussing death in this letter. The difficulty here is sliding into fatalism. For instance, if you are informed that you have cancer, it is tempting to become 'wise' and will your own death, but lots of people fight it, and win. |
| 13317 | Philosophy aims at happiness [Seneca] |
| Full Idea: Philosophy takes as her aim the state of happiness. | |
| From: Seneca the Younger (Letters from a Stoic [c.60], 090) | |
| A reaction: A startlingly forthright view. It seems to neglect what I take to be the main aim of philosophy, which is to achieve understanding. I presume true happiness would follow from that. Seneca must now explain why soporific pleasure is wrong. |
| 13293 | What philosophy offers humanity is guidance [Seneca] |
| Full Idea: Shall I tell you what philosophy holds out for humanity? Counsel. | |
| From: Seneca the Younger (Letters from a Stoic [c.60], 048) | |
| A reaction: See Quine for a flat modern denial of this claim (Idea 9764). There is a modern tendency to see ethics and political thought operating at a meta- or metameta- level. I take the main ethical theories to be very illuminating of real life. |
| 13309 | That something is a necessary condition of something else doesn't mean it caused it [Seneca] |
| Full Idea: There's no reason for you to assume that, X being something without which Y could never have come about, Y came about as a result of the assistance of X. | |
| From: Seneca the Younger (Letters from a Stoic [c.60], 088) | |
| A reaction: This thought originates with Carneades, reported by Cicero. This is a clear message to the likes of Mackie, who are in danger of thinking that giving the preconditions of something is sufficient to give its causes. |
| 13313 | Even philosophers have got bogged down in analysing tiny bits of language [Seneca] |
| Full Idea: Even the philosophers have descended to the level of drawing distinctions between the uses of different syllables and discussing the proper meanings of prepositions and conjunctions. | |
| From: Seneca the Younger (Letters from a Stoic [c.60], 088) | |
| A reaction: How wonderfully prescient! The vast industry of modern philosophy of language exactly fits Seneca's description. I don't quite share his contempt, of course, and I think Seneca would have a bit of sympathy with modern analysis (just a bit!). |
| 11283 | There is pure deductive reasoning, and explanatory demonstration reasoning [Aristotle, by Politis] |
| Full Idea: Aristotle distinguishes between deductive reasoning (sullogismos) and demonstration (apodeixis). All demonstration is deductive reasoning, but not all deductive reasoning is demonstration. | |
| From: report of Aristotle (Posterior Analytics [c.327 BCE], Bk I.2) by Vassilis Politis - Aristotle and the Metaphysics 5.3 | |
| A reaction: This sounds not far off the distinction between single-turnstile (formal proof) and double-turnstile (semantic consequence). Politis says, though, that the key point is the demonstration is explanatory. |
| 1672 | Maybe everything could be demonstrated, if demonstration can be reciprocal or circular [Aristotle] |
| Full Idea: Some optimists think understanding arises only through demonstration, but say there could be demonstration of everything, for it is possible to demonstrate in a circle or reciprocally. | |
| From: Aristotle (Posterior Analytics [c.327 BCE], 72b16) | |
| A reaction: I'm an optimist in this sense, though what is being described would probably best be called 'large-scale coherence'. Two reciprocal arguments look bad, but a hundred look good. |
| 1684 | Two falsehoods can be contrary to one another [Aristotle] |
| Full Idea: There are falsehoods which are contrary to one another and cannot be the case together e.g. that a man is a horse or a cow. | |
| From: Aristotle (Posterior Analytics [c.327 BCE], 88a29) |
| 12384 | Definition by division needs predicates, which are well ordered and thorough [Aristotle] |
| Full Idea: To establish a definition through division, you must aim for three things: you must take what is predicated in what the thing is; you must order these items as first or second; and you must ensure that these are all there are. | |
| From: Aristotle (Posterior Analytics [c.327 BCE], 97a23) | |
| A reaction: This gives an indication of the thoroughness that Aristotle expects from a definition. They aren't like dictionary definitions of words. He expects definitions to often be very lengthy (see Idea 12292). |
| 9066 | You can define objects by progressively identifying what is the same and what is different [Aristotle] |
| Full Idea: Find what is in common among items similar and undifferentiated, then do the same for items of the same kind as the first group but a different form, and so on, till you come to a single account: this will be the definition of the object. | |
| From: Aristotle (Posterior Analytics [c.327 BCE], 97b07-14) | |
| A reaction: [His example is distinguishing 'magnanimity' from 'indifference to fortune' among people] Presumably this process works for the formation of new concepts (e.g. in biology), as well as for the definition of familiars in terms of other familiars. |
| 12145 | Definitions are of what something is, and that is universal [Aristotle] |
| Full Idea: Definitions are thought to be of what something is, and what something is is in every case universal and positive. | |
| From: Aristotle (Posterior Analytics [c.327 BCE], 90b05) | |
| A reaction: This is exhibit A for those who think that Aristotelian essences concern the genus, rather than the particular. I suspect that this idea is best expressed as 'all we can say by way of definition of a particular thing involves the use of universals'. |
| 12075 | An Aristotelian definition is causal [Aristotle, by Witt] |
| Full Idea: An Aristotelian definition is causal. | |
| From: report of Aristotle (Posterior Analytics [c.327 BCE], Bk II.2) by Charlotte Witt - Substance and Essence in Aristotle 1.5 | |
| A reaction: [She refers us to Posterior Analytics II.2] This is important if we are tempted to follow a modern line of saying that we want Aristotelian essences, and that these are definitions. We ain't thinking of dictionaries. |
| 12382 | What it is and why it is are the same; screening defines and explains an eclipse [Aristotle] |
| Full Idea: What it is and why it is are the same. What is an eclipse? Privation of light from the moon by screening of the earth. Why is there an eclipse? ...What is a harmony? A numerical ratio between high and low. Why do the high and low harmonize? The ratio. | |
| From: Aristotle (Posterior Analytics [c.327 BCE], 90a15) | |
| A reaction: This is right at the heart of Aristotelian essentialism, and (I take it) modern scientific essentialism. If you fully know what cigarette tars are, and what human cell structure is, you understand immediately why cigarettes cause cancer. |
| 1668 | An axiom is a principle which must be understood if one is to learn anything [Aristotle] |
| Full Idea: An axiom is a principle which must be grasped if anyone is going to learn anything whatever. | |
| From: Aristotle (Posterior Analytics [c.327 BCE], 72a17) |
| 12376 | Demonstrations by reductio assume excluded middle [Aristotle] |
| Full Idea: Demonstrations by reduction to the impossible assume that everything is asserted or denied. | |
| From: Aristotle (Posterior Analytics [c.327 BCE], 77a23) | |
| A reaction: This sounds like the lynchpin of classical logic. |
| 12373 | Something holds universally when it is proved of an arbitrary and primitive case [Aristotle] |
| Full Idea: Something holds universally when it is proved of an arbitrary and primitive case. | |
| From: Aristotle (Posterior Analytics [c.327 BCE], 73b33) | |
| A reaction: A key idea in mathematical logic, but it always puzzles me. If you snatch a random person in London, and they are extremely tall, does that prove that people of London are extremely tall? How do we know the arbitrary is representative? |
| 12363 | Everything is either asserted or denied truly [Aristotle] |
| Full Idea: Of the fact that everything is either asserted or denied truly, we must believe that it is the case. | |
| From: Aristotle (Posterior Analytics [c.327 BCE], 71a14) | |
| A reaction: Presumably this means that every assertion which could possibly be asserted must come out as either true or false. This will have to include any assertions with vague objects or predicates, and any universal assertions, and negative assertions. |
| 13004 | Aristotle's axioms (unlike Euclid's) are assumptions awaiting proof [Aristotle, by Leibniz] |
| Full Idea: Aristotle's way with axioms, rather than Euclid's, is as assumptions which we are willing to agree on while awaiting an opportunity to prove them | |
| From: report of Aristotle (Posterior Analytics [c.327 BCE], 76b23-) by Gottfried Leibniz - New Essays on Human Understanding 4.07 | |
| A reaction: Euclid's are understood as basic self-evident truths which will be accepted by everyone, though the famous parallel line postulate undermined that. The modern view of axioms is a set of minimum theorems that imply the others. I like Aristotle. |
| 12377 | Mathematics is concerned with forms, not with superficial properties [Aristotle] |
| Full Idea: Mathematics is concerned with forms [eide]: its objects are not said of any underlying subject - for even if geometrical objects are said of some underlying subject, still it is not as being said of an underlying subject that they are studied. | |
| From: Aristotle (Posterior Analytics [c.327 BCE], 79a08) | |
| A reaction: Since forms turn out to be essences, in 'Metaphysics', this indicates an essentialist view of mathematics. |
| 12372 | The essence of a triangle comes from the line, mentioned in any account of triangles [Aristotle] |
| Full Idea: Something holds of an item in itself if it holds of it in what it is - e.g., line of triangles and point of lines (their essence comes from these items, which inhere in the account which says what they are). | |
| From: Aristotle (Posterior Analytics [c.327 BCE], 73a35) | |
| A reaction: A helpful illustration of how a definition gives us the essence of something. You could not define triangles without mentioning straight lines. The lines are necessary features, but they are essential for any explanation, and for proper understanding. |
| 12369 | A unit is what is quantitatively indivisible [Aristotle] |
| Full Idea: Arithmeticians posit that a unit is what is quantitatively indivisible. | |
| From: Aristotle (Posterior Analytics [c.327 BCE], 72a22) | |
| A reaction: Presumably indeterminate stuff like water is non-quantitatively divisible (e.g. Moses divides the Red Sea), as are general abstracta (curved shapes from rectilinear ones). Does 'quantitative' presupposes units, making the idea circular? |
| 18910 | To seek truth, study the real connections between subjects and attributes [Aristotle] |
| Full Idea: If, however, one is aiming at truth, one must be guided by the real connexions of subjects and attributes. | |
| From: Aristotle (Posterior Analytics [c.327 BCE], 81b22), quoted by George Engelbretsen - Trees, Terms and Truth 3 | |
| A reaction: I take this to be a warning that predicates that indicate mere 'Cambridge properties' (such as relations, locations, coincidences etc) have nothing to do with ontology. See Shoemaker on properties. |
| 1675 | Separate Forms aren't needed for logic, but universals (one holding of many) are essential [Aristotle] |
| Full Idea: There need be no forms (one item apart from the many) for demonstrations. But there must be universals, where one thing holds of the many. Without universals there are no middle terms, and so no demonstrations. | |
| From: Aristotle (Posterior Analytics [c.327 BCE], 77a05) |
| 1677 | We can forget the Forms, as they are irrelevant, and not needed in giving demonstrations [Aristotle] |
| Full Idea: We can say goodbye to the forms. They are nonny-noes; and if there are any they are irrelevant - for demonstrations are not concerned with them. | |
| From: Aristotle (Posterior Analytics [c.327 BCE], 83a34) |
| 1687 | Why are being terrestrial and a biped combined in the definition of man, but being literate and musical aren't? [Aristotle] |
| Full Idea: Why will a man be a two-footed terrestrial animal and not an animal and terrestrial? Assumptions do not make it necessary that what is predicated form a unity - rather, it is as if the same man were musical and literate. | |
| From: Aristotle (Posterior Analytics [c.327 BCE], 92a30) |
| 1681 | Units are positionless substances, and points are substances with position [Aristotle] |
| Full Idea: A unit is a positionless substance, and a point a substance having position. | |
| From: Aristotle (Posterior Analytics [c.327 BCE], 87a36) |
| 12146 | Definitions recognise essences, so are not themselves essences [Aristotle] |
| Full Idea: If a definition is the recognition of some essence, it is clear that such items are not essences. | |
| From: Aristotle (Posterior Analytics [c.327 BCE], 90b17) | |
| A reaction: So definitions are not themselves essences (as some modern thinkers claim). The idea seems obvious to me, but it is a warning against a simplistic view of Aristotelian essences, and a reminder that such things are real, not verbal. |
| 17039 | The predicates of a thing's nature are necessary to it [Aristotle] |
| Full Idea: Whatever is predicated in what something is is necessary. | |
| From: Aristotle (Posterior Analytics [c.327 BCE], 96b03) | |
| A reaction: This does NOT say that the essence is just the necessities. He goes on to say to say separately that certain properties of a triplet are part of the essence, as well as being necessary. This shows the nature of a thing is also necessary. |
| 11994 | Aristotelian essences are properties mentioned at the starting point of a science [Aristotle, by Kung] |
| Full Idea: As Aristotle uses the term 'essence', only those properties which are mentioned in or relatively close to the starting points of the science will be essential. | |
| From: report of Aristotle (Posterior Analytics [c.327 BCE]) by Joan Kung - Aristotle on Essence and Explanation II | |
| A reaction: I take this to be the correct way to understand Aristotelian essence - as something understood by its role in scientific explanations. We may, of course, work back to the starting point of a science, by disentangling the mess in the middle. |
| 12381 | What is necessary cannot be otherwise [Aristotle] |
| Full Idea: What is necessary cannot be otherwise. | |
| From: Aristotle (Posterior Analytics [c.327 BCE], 88b32) | |
| A reaction: If the next interesting question is the source of necessity, then the question seems to be 'what prevents it from being otherwise?'. |
| 1690 | A stone travels upwards by a forced necessity, and downwards by natural necessity [Aristotle] |
| Full Idea: There are two types of necessity, one according to nature and impulse, the other by force and contrary to impulse. A stone travels upwards and downwards from different necessities. | |
| From: Aristotle (Posterior Analytics [c.327 BCE], 94b38) |
| 12378 | The reason why is the key to knowledge [Aristotle] |
| Full Idea: Study of the reason why has the most importance for knowledge. | |
| From: Aristotle (Posterior Analytics [c.327 BCE], 79a24) | |
| A reaction: I take the study of reasons for belief to be much more central to epistemology than finding ways to answer radical sceptics about the basic possibility of knowledge. |
| 12072 | For Aristotle knowledge is explanatory, involving understanding, and principles or causes [Aristotle, by Witt] |
| Full Idea: For Aristotle, knowledge is explanatory, for to know something is to understand it, and to understand something is to grasp its principles or causes. | |
| From: report of Aristotle (Posterior Analytics [c.327 BCE]) by Charlotte Witt - Substance and Essence in Aristotle 1.2 | |
| A reaction: Thus the kind of 'knowledge' displayed in quiz shows would not count as knowledge at all, if it was mere recall of facts. To know is to be able to explain, which is to be able to teach. See Idea 11241. |
| 12073 | 'Episteme' means grasping causes, universal judgments, explanation, and teaching [Aristotle, by Witt] |
| Full Idea: For Aristotle, a person who has 'episteme' grasps the cause of a given phenomenon, can make a universal judgment about it, can explain it, and can teach others about it. | |
| From: report of Aristotle (Posterior Analytics [c.327 BCE]) by Charlotte Witt - Substance and Essence in Aristotle 1.2 | |
| A reaction: This I take to be the context in which we should understand what Aristotle means by an 'essence' - it is the source of all of the above, so it both makes a thing what it is, and explains why it shares features with other such things. |
| 12370 | Some understanding, of immediate items, is indemonstrable [Aristotle] |
| Full Idea: Not all understanding is demonstrative: rather, in the case of immediate items understanding is indemonstrable. | |
| From: Aristotle (Posterior Analytics [c.327 BCE], 72b19) | |
| A reaction: These are the foundations of Aristotle's epistemology, and I take it that they can be both empiricist and rationalist - sense experiences, and a priori intuitions. |
| 12364 | We understand a thing when we know its explanation and its necessity [Aristotle] |
| Full Idea: We understand something simpliciter when we think we know of the explanation because of which the object holds that it is its explanation, and also that it is not possible for it to be otherwise. | |
| From: Aristotle (Posterior Analytics [c.327 BCE], 71b10) | |
| A reaction: The second half sounds odd, since we ought to understand that something could have been otherwise, and knowing whether or not it could have been otherwise is part of the understanding. It sounds like Spinozan determinism. |
| 12366 | We only understand something when we know its explanation [Aristotle] |
| Full Idea: We only understand something when we know its explanation. | |
| From: Aristotle (Posterior Analytics [c.327 BCE], 71b30) | |
| A reaction: If we believe that the whole aim of philosophy is 'understanding' (Idea 543) - and if it isn't then I am not sure what the aim is, and alternative aims seem a lot less interesting - then we should care very much about explanations, as well as reasons. |
| 1685 | No one has mere belief about something if they think it HAS to be true [Aristotle] |
| Full Idea: No one holds something as an opinion when he thinks that it is impossible for it to be otherwise - for then he thinks he understands it. | |
| From: Aristotle (Posterior Analytics [c.327 BCE], 89a07) |
| 1673 | Knowledge proceeds from principles, so it is hard to know if we know [Aristotle] |
| Full Idea: It is difficult to know whether you know something or not. For it is difficult to know whether or not our knowledge of something proceeds from its principles - and this is what it is to know something. | |
| From: Aristotle (Posterior Analytics [c.327 BCE], 76a25) |
| 12379 | You cannot understand anything through perception [Aristotle] |
| Full Idea: You cannot understand anything through perception. Demonstrations are universal, and universals cannot be perceived. | |
| From: Aristotle (Posterior Analytics [c.327 BCE], 87b28) |
| 16725 | Some knowledge is lost if you lose a sense, and there is no way the knowledge can be replaced [Aristotle] |
| Full Idea: The loss of any one of the senses entails the loss of a corresponding portion of knowledge, and since we learn either by induction or by demonstration, this knowledge cannot be acquired. | |
| From: Aristotle (Posterior Analytics [c.327 BCE], 81a37) | |
| A reaction: This suggests Jackson's 'knowledge argument', that raw experience contains some genuine knowledge, for which there is no mechanistic substitute. Not that I accept…. |
| 23309 | Aristotle's concepts of understanding and explanation mean he is not a pure empiricist [Aristotle, by Frede,M] |
| Full Idea: It is a certain notion of understanding and, correspondingly, explanation which makes Aristotle think that knowledge, properly speaking, could not be a matter of mere experience. | |
| From: report of Aristotle (Posterior Analytics [c.327 BCE]) by Michael Frede - Aristotle's Rationalism p.160 | |
| A reaction: Frede says this means that Aristotle is a rationalist, though few empiricists think understanding is 'merely' a matter of experience. My own epistemology is Explanatory Empiricism, which I see as more empiricist than rationalist. |
| 1693 | Animals may have some knowledge if they retain perception, but understanding requires reasons to be given [Aristotle] |
| Full Idea: In some animals the perception is retained, and in some not. Without retention knowledge is impossible. Some animals go further and form an account based on the perception. This leads to memory and experience, and so to either skill or understanding. | |
| From: Aristotle (Posterior Analytics [c.327 BCE], 99b35-) |
| 9067 | Many memories of the same item form a single experience [Aristotle] |
| Full Idea: When it occurs often in connection with the same item, ..memories which are many in number form a single experience. | |
| From: Aristotle (Posterior Analytics [c.327 BCE], 100a05) | |
| A reaction: This is Aristotle at his most empirical. He is not describing an operation of the understanding, but a process of association. The process he alludes to is at the heart of the abstractionist view of concept-formation. |
| 1671 | Sceptics say justification is an infinite regress, or it stops at the unknowable [Aristotle] |
| Full Idea: Sceptics say that there is either an infinite regress of ideas based on one another, or things come to a stop at primitives which are unknowable (because they can't be demonstrated). | |
| From: Aristotle (Posterior Analytics [c.327 BCE], 72b09) | |
| A reaction: This is one strand of what eventually becomes the classic Agrippa's Trilemma (Idea 8850). For Aristotle's view on this one, see Idea 562. |
| 1670 | When you understand basics, you can't be persuaded to change your mind [Aristotle] |
| Full Idea: Anyone who understands anything simpliciter (as basic) must be incapable of being persuaded to change his mind. | |
| From: Aristotle (Posterior Analytics [c.327 BCE], 72b04) | |
| A reaction: A typical Aristotle test which seems rather odd to us. Surely I can change my mind, and decide that something is not basic after all? But, says Aristotle, then you didn't really think it was basic. |
| 1667 | Premises must be true, primitive and immediate, and prior to and explanatory of conclusions [Aristotle] |
| Full Idea: Demonstrative understanding must proceed from items which are true and primitive and immediate and more familiar and prior to and explanatory of the conclusions. | |
| From: Aristotle (Posterior Analytics [c.327 BCE], 71b22) |
| 24068 | Demonstration is more than entailment, as the explanatory order must match the causal order [Aristotle, by Koslicki] |
| Full Idea: Aristotle's demonstration encompasses more than deductive entailment, in that the explanatory order of priority represented in a successful demonstration must mirror precisely the causal order of priority in the phenomena in question. | |
| From: report of Aristotle (Posterior Analytics [c.327 BCE]) by Kathrin Koslicki - Form, Matter and Substance 4.5 | |
| A reaction: Interesting. I presume this is correct, but is not an aspect I had registered. In Metaphysics his essentialist explanations are causal, so it all hangs together. |
| 17310 | Aristotle gets asymmetric consequence from demonstration, which reflects real causal priority [Aristotle, by Koslicki] |
| Full Idea: In Aristotle's system, the relevant notion of asymmetric consequence that is operative in his model of scientific explanation is that of demonstration. ...It is a theoretical/linguistic reflection of an asymmetric real-world relation of causal priority. | |
| From: report of Aristotle (Posterior Analytics [c.327 BCE]) by Kathrin Koslicki - Varieties of Ontological Dependence 7.3 n7 | |
| A reaction: The asymmetry is required for explanation, and for grounding. |
| 21359 | Aristotle doesn't actually apply his theory of demonstration to his practical science [Leroi on Aristotle] |
| Full Idea: There is a conflict between the syllogistic theory of demonstration of the Posterior Analytics, with its austere programme of certainties, and how Aristotle actually does science. | |
| From: comment on Aristotle (Posterior Analytics [c.327 BCE]) by Armand Marie LeRoi - The Lagoon: how Aristotle invented science 104 | |
| A reaction: Leroi observes that there are no demonstrations anywhere in the biological writings. Biology probably lends itself least to such an approach. |
| 12365 | We can know by demonstration, which is a scientific deduction leading to understanding [Aristotle] |
| Full Idea: We know things through demonstration, by which I mean a scientific deduction, and by 'scientific' I mean a deduction by possessing which we understand something. | |
| From: Aristotle (Posterior Analytics [c.327 BCE], 71b17) | |
| A reaction: This is a distinctively Aristotelian account of what science aims at, and which seems to have dropped out of modern accounts of science, which are still under the influence of logical positivism. Time to revive it. |
| 10918 | Demonstrative understanding rests on necessary features of the thing in itself [Aristotle] |
| Full Idea: If demonstrative understanding proceeds from necessary principles, and whatever holds of an object in itself is necessary, then it is clear that demonstrative deductions will proceed from certain items of this sort. | |
| From: Aristotle (Posterior Analytics [c.327 BCE], 74b05-) | |
| A reaction: This is the characterization of the essence of something in terms of what counts as a good explanation of that thing. Although explanation is a bit subjective, I like this approach, because you will dig down to the source of the powers of the thing. |
| 12374 | Demonstrations must be necessary, and that depends on the middle term [Aristotle] |
| Full Idea: If you understand something demonstratively, it must hold from necessity, so it is plain that your demonstration must proceed through a middle term which is necessary. | |
| From: Aristotle (Posterior Analytics [c.327 BCE], 75a13) | |
| A reaction: How can a middle 'term' be necessary, if it is not a proposition? Presumably Socrates is necessarily a man, and men are necessarily mortal, so it is the predication which is necessary. |
| 12148 | Demonstrations are syllogisms which give explanations [Aristotle] |
| Full Idea: Demonstrations are probative deductions [sullogismos] which give the explanation [aitias] and the reason why. | |
| From: Aristotle (Posterior Analytics [c.327 BCE], 85b24) | |
| A reaction: This notion seems to have slipped out of modern philosophy of science, because (while scientists have just pressed on) philosophers of science have raised so many sceptical questions that they have, I would say, lost the plot. |
| 1680 | Demonstration is better with fewer presuppositions, and it is quicker if these are familiar [Aristotle] |
| Full Idea: A demonstration is superior if it depends on fewer suppositions or propositions - for if these are familiar, knowledge will come more quickly, and this is preferable. | |
| From: Aristotle (Posterior Analytics [c.327 BCE], 86a35) |
| 12147 | The principles of demonstrations are definitions [Aristotle] |
| Full Idea: The principles of demonstrations are definitions. | |
| From: Aristotle (Posterior Analytics [c.327 BCE], 90b25) | |
| A reaction: This I take to be a key idea linking Aristotle's desire to understand the world, by using demonstrations to reach good explanations. Definitions turn out to rest on essences, so our understanding of the world rests on essences. |
| 12383 | There must be definitions before demonstration is possible [Aristotle] |
| Full Idea: There is no demonstration of anything of which there is no definition. Definitions are of what something is, i.e. of its essence, but all demonstrations clearly suppose and assume what a thing is. | |
| From: Aristotle (Posterior Analytics [c.327 BCE], 90b30) | |
| A reaction: Note that while essentialism rests on definitions, the job is not yet complete once the definitions are done. With good definitions, it should be easy to show how the pieces of the jigsaw fit together. |
| 1691 | Aim to get definitions of the primitive components, thus establishing the kind, and work towards the attributes [Aristotle] |
| Full Idea: Divide a whole into its primitives, then try to get definitions of these. Thus you establish the kind, and then study the attributes through the primitive common items. | |
| From: Aristotle (Posterior Analytics [c.327 BCE], 96b16) |
| 12371 | A demonstration is a deduction which proceeds from necessities [Aristotle] |
| Full Idea: A demonstration is a deduction which proceeds from necessities. | |
| From: Aristotle (Posterior Analytics [c.327 BCE], 73a24) | |
| A reaction: Elsewhere he tells us that demonstration that brings understanding (Idea 12365), so this is an interesting gloss. He says that the middle term of the syllogism gives the understanding, but necessities reside in the whole propositions of the premisses. |
| 1679 | Universal demonstrations are about thought; particular demonstrations lead to perceptions [Aristotle] |
| Full Idea: Universal demonstrations are objects of thought, particular demonstrations terminate in perception. | |
| From: Aristotle (Posterior Analytics [c.327 BCE], 86a30) |
| 1674 | All demonstration is concerned with existence, axioms and properties [Aristotle] |
| Full Idea: All demonstrative science [apodeiktike episteme] is concerned with three things: what it posits to exist (the kind), the axioms (primitives basic to demonstration), and the attributes. | |
| From: Aristotle (Posterior Analytics [c.327 BCE], 76b12) |
| 1683 | We learn universals from many particulars [Aristotle] |
| Full Idea: It is from many particulars that the universal becomes plain. Universals are valuable because they make the explanation plain. | |
| From: Aristotle (Posterior Analytics [c.327 BCE], 88a05) |
| 12380 | Universals are valuable because they make the explanations plain [Aristotle] |
| Full Idea: Universals are valuable because they make the explanations plain. | |
| From: Aristotle (Posterior Analytics [c.327 BCE], 88a06) | |
| A reaction: Everything in Aristotle comes back to human capacity to understand. There seems to be an ideal explanation consisting entirely of particulars, but humans are not equipped to grasp it. We think in a broad brush way. |
| 12367 | What is most universal is furthest away, and the particulars are nearest [Aristotle] |
| Full Idea: What is most universal is furthest away, and the particulars are nearest. | |
| From: Aristotle (Posterior Analytics [c.327 BCE], 72a05) | |
| A reaction: This is the puzzle that bother Aristotle about explanation, that we can only grasp the universals, when we want to explain the particulars. |
| 12385 | Are particulars explained more by universals, or by other particulars? [Aristotle] |
| Full Idea: Which of the middle terms is explanatory for the particulars - the one which is primitive in the direction of the universal, or the one which is primitive in the direction of the particular? | |
| From: Aristotle (Posterior Analytics [c.327 BCE], 99b09) | |
| A reaction: I'm not clear about this, but it shows Aristotle wrestling with the issue of whether explanations are of particulars or universals, and whether they employ particulars as well as employing universals. The particular must be defined! |
| 1689 | Explanation is of the status of a thing, inferences to it, initiation of change, and purpose [Aristotle] |
| Full Idea: There are four sorts of explanation: what it is to be something, that if certain items hold it is necessary for this to hold, what initiated the change, and the purpose. | |
| From: Aristotle (Posterior Analytics [c.327 BCE], 94a21) | |
| A reaction: This might be summed up as: 'we want to know the essence, the necessary conditions, the cause, and the purpose'. Can anyone improve on that as the aims of explanation? The second explanation (necessary preconditions) isn't in 'Physics' - Idea 8332. |
| 1686 | What we seek and understand are facts, reasons, existence, and identity [Aristotle] |
| Full Idea: The things we seek are equal in number to those we understand: the fact, the reason why, if something is, and what something is. | |
| From: Aristotle (Posterior Analytics [c.327 BCE], 89b24) |
| 13297 | To the four causes Plato adds a fifth, the idea which guided the event [Seneca] |
| Full Idea: To the four Aristotelian causes Plato adds a fifth in the model - what he himself calls the 'idea' - this being what the sculptor had constantly before his eyes as he executed the intended work. | |
| From: Seneca the Younger (Letters from a Stoic [c.60], 065) | |
| A reaction: A very interesting interpretation. I take the four 'causes' to be primarily the four 'explanations', and it exactly fits how we should understand Plato, as offer a crucial underlying explanation. The statue is Aristotle's example. |
| 12357 | Explanation and generality are inseparable [Aristotle, by Wedin] |
| Full Idea: For Aristotle, explanation and generality are fellow-travellers. | |
| From: report of Aristotle (Posterior Analytics [c.327 BCE]) by Michael V. Wedin - Aristotle's Theory of Substance X.11 | |
| A reaction: This isn't 'lawlike' explanation, but it is interestingly close to it. It seems to be based on the fact that predicates are universals, so we can only state truths in general terms. |
| 1669 | The foundation or source is stronger than the thing it causes [Aristotle] |
| Full Idea: Something always holds better because of that because of which it holds - e.g. that because of which we love something is better loved. | |
| From: Aristotle (Posterior Analytics [c.327 BCE], 72a30) |
| 1678 | Universals give better explanations, because they are self-explanatory and primitive [Aristotle] |
| Full Idea: Universals are more explanatory (for something which holds in itself is itself explanatory of itself; and universals are primitive; hence universals are explanatory) - so universal demonstrations are better. | |
| From: Aristotle (Posterior Analytics [c.327 BCE], 85b25) |
| 9068 | Perception creates primitive immediate principles by building a series of firm concepts [Aristotle] |
| Full Idea: Primitive immediate principles ...come about from perception - as in a battle, when a rout has occurred, first one man makes a stand, then another, and then another, until a position of strength is reached. | |
| From: Aristotle (Posterior Analytics [c.327 BCE], 100a12) | |
| A reaction: Philosophers don't create imagery like that any more. This empiricist account of how concepts and universals are created is part of a campaign against Plato's theory of forms. [Idea 9069 continues his idea] |
| 9069 | A perception lodging in the soul creates a primitive universal, which becomes generalised [Aristotle] |
| Full Idea: When one undifferentiated item in perception makes a stand, there is a primitive universal in the soul; for although you perceive particulars, perception is of universals - e.g. of man, not of Callias the man. One animal makes a stand, until animal does. | |
| From: Aristotle (Posterior Analytics [c.327 BCE], 100a15-) | |
| A reaction: This is the quintessential account of abstractionism, with the claim that primitive universals arise directly in perception, but only in repeated perception. How the soul does it is a mystery to Aristotle, just as associations are a mystery to Hume. |
| 13307 | If everything can be measured, try measuring the size of a man's soul [Seneca] |
| Full Idea: Nothing's outside your scope when it comes to measurement. Well, if you're such an expert, measure a man's soul; tell me how large or how small that is. | |
| From: Seneca the Younger (Letters from a Stoic [c.60], 088) | |
| A reaction: This is Descartes's non-spatial argument, which I take to be one of the four main props to his mind-body dualism. As always, it is expressed with beautiful concision by Seneca. |
| 9070 | We learn primitives and universals by induction from perceptions [Aristotle] |
| Full Idea: We must get to know the primitives by induction; for this is the way in which perception instils universals. | |
| From: Aristotle (Posterior Analytics [c.327 BCE], 100b04) | |
| A reaction: This statement is so strongly empirical it could have come from John Stuart Mill. The modern post-Fregean view of universals is essentially platonist - that they have a life and logic of their own, and their method of acquisition is irrelevant. |
| 21399 | Referring to a person, and speaking about him, are very different [Seneca] |
| Full Idea: It makes a very great difference whether you refer to the person directly, or speak about him. | |
| From: Seneca the Younger (Letters from a Stoic [c.60], 117.13), quoted by A.A. Long - Hellenistic Philosophy 4.3.2 | |
| A reaction: We seem to think that the distinctiveness of reference was first spotted by Frege. Not so. |
| 12368 | Negation takes something away from something [Aristotle] |
| Full Idea: The part of a contradictory pair which says something of something is an affirmation; the part which takes something from something is a negation. | |
| From: Aristotle (Posterior Analytics [c.327 BCE], 72a14) | |
| A reaction: So affirmation is predication about an object ['Fa'], and negation is denial of predication. We have a scope problem: there is nothing which is F [¬∃x(Fx)], or there is a thing which is not-F [∃x(¬Fx)]. Aristotle seems to mean the latter. |
| 1692 | If you shouldn't argue in metaphors, then you shouldn't try to define them either [Aristotle] |
| Full Idea: If you should not argue in metaphors, it is plain too that you should neither define by metaphors nor define what is said in metaphors; for then you will necessarily argue in metaphors. | |
| From: Aristotle (Posterior Analytics [c.327 BCE], 97b37) | |
| A reaction: Impeccable logic, but seeing a similarity can be a wonderful shortcut to seeing a great truth. |
| 13325 | Trouble in life comes from copying other people, which is following convention instead of reason [Seneca] |
| Full Idea: One of the causes of the troubles that beset us is the way our lives are guided by the example of others; instead of being set to rights by reason we're seduced by convention. | |
| From: Seneca the Younger (Letters from a Stoic [c.60], 123) | |
| A reaction: An interesting practical spin and critique of the standard metaethical idea that morality is just convention. If you think morality is convention, presumably your moral duty is to imitate your neighbours. Nice deconstruction. |
| 22239 | Humans acquired the concept of virtue from an analogy with bodily health and strength [Seneca, by Allen] |
| Full Idea: Seneca held that human beings owe the original acquisition of the concept of virtue to an analogy with bodily health and strength | |
| From: report of Seneca the Younger (Letters from a Stoic [c.60], 120.5) by James Allen - Soul's Virtue and the Health of the Body p.76 | |
| A reaction: This is an unusual view, even for a stoic, but shows how close the concepts of health and virtue were. Notice that it is strength as well as health. Plato just emphasises mental and physical harmony. |
| 13294 | We know death, which is like before birth; ceasing to be and never beginning are the same [Seneca] |
| Full Idea: I already know what death is like - it will be the same after me as it was before me. ..Only an utter idiot would think a lamp was worse off when it was put out than before it was lit. ..What does it matter whether you cease to be or never begin? | |
| From: Seneca the Younger (Letters from a Stoic [c.60], 054) | |
| A reaction: These sentiments are, interestingly, derived from the epicureans, rather than from the stoic tradition, but to us they probably look close together, where they looked like opponents at the time. |
| 13299 | Living is nothing wonderful; what matters is to die well [Seneca] |
| Full Idea: There's nothing so very great about living - all your slaves and all the animals do it. What is, however, a great thing is to die in a manner which is honourable, enlightened and courageous. | |
| From: Seneca the Younger (Letters from a Stoic [c.60], 077) | |
| A reaction: You get the feeling that Seneca actually thought suicide was better than a natural death. Did he actually seek his own death? It is an odd interpretation of his own stoic injunction to 'live according to nature'. |
| 13300 | It is as silly to lament ceasing to be as to lament not having lived in the remote past [Seneca] |
| Full Idea: Wouldn't you think a man a prize fool if he burst into tears because he didn't live a thousand years ago? A man is such a fool for shedding tears because he isn't going to be alive a thousand years from now. | |
| From: Seneca the Younger (Letters from a Stoic [c.60], 077) | |
| A reaction: These thoughts are traditional, dating back to Epicurus, but Seneca is exceptionally going at finding new variations and examples to reinforce the basic thought. |
| 13321 | Is anything sweeter than valuing yourself more when you find you are loved? [Seneca] |
| Full Idea: Can anything be sweeter than to find that you are so dear to your wife that this makes you dearer to yourself? | |
| From: Seneca the Younger (Letters from a Stoic [c.60], 104) | |
| A reaction: Another lovely penetrating remark from Seneca. I suppose a symptom of low self-esteem might be 'why does she love someone as worthless as me?', but that would be unusual. |
| 13292 | Selfishness does not produce happiness; to live for yourself, live for others [Seneca] |
| Full Idea: No one can lead a happy life if he thinks only of himself and turns everything to his own purposes. You should live for the other person if you wish to live for yourself. | |
| From: Seneca the Younger (Letters from a Stoic [c.60], 048) | |
| A reaction: It is important to see this as a key aspect of the ancient aspiration to virtue. The end result is not far from Christianity. It is simplistic to see the quest for virtue as a crass self-obsessed quest for self-improvement. We are social. |
| 13303 | A man is as unhappy as he has convinced himself he is [Seneca] |
| Full Idea: A man is as unhappy as he has convinced himself he is. | |
| From: Seneca the Younger (Letters from a Stoic [c.60], 078) | |
| A reaction: Seneca is a very penetrating thinker about ordinary life - an aspect of philosophy which is nowadays totally neglected by the most eminent philosophers. |
| 13302 | Life is like a play - it is the quality that matters, not the length [Seneca] |
| Full Idea: As it is with a play, so it is with life - what matters is not how long the acting lasts, but how good it is. | |
| From: Seneca the Younger (Letters from a Stoic [c.60], 077) | |
| A reaction: A very nice epigram, culminating the wonderful Letter 77 on the subject of death. A play needs to be a decent length if it is to exhibit its qualities. It would be heartbreaking if all of Shakespeare's plays were just 20-minute sketches. |
| 13301 | We are scared of death - except when we are immersed in pleasure! [Seneca] |
| Full Idea: You are scared of death - but how heedless of it you are while you are dealing with a dish of choice mushrooms! | |
| From: Seneca the Younger (Letters from a Stoic [c.60], 077) | |
| A reaction: A beautifully simple observation, from the greatest philosopher of death. Maybe hospices should concentrate on sex, drugs and rock and roll. |
| 13323 | The whole point of pleasure-seeking is novelty, and abandoning established ways [Seneca] |
| Full Idea: The whole object of luxurious living is the delight it takes in irregular ways and in not merely departing from the correct course but going to the farthest point away from it, and in eventually even taking a stand diametrically opposed to it. | |
| From: Seneca the Younger (Letters from a Stoic [c.60], 122) | |
| A reaction: A rather conservative and puritanical remark, but worthy of contemplation even for committed hedonists. It is just a sad facts that most pleasures diminish with familiarity. Small children make delightful remarks. Imagine if they repeated them. |
| 13318 | Nature doesn't give us virtue; we must unremittingly pursue it, as a training and an art [Seneca] |
| Full Idea: Nature does not give a man virtue; the process of becoming a good man is an art. ...Virtue only comes to a character which has been thoroughly schooled and trained and brought to a pitch of perfection by unremitting practice. | |
| From: Seneca the Younger (Letters from a Stoic [c.60], 090) | |
| A reaction: This is an important gloss from a leading stoic on the slogan of 'live according to nature'. One might say that the natural life must be 'tracked' (as Philip Larkin says we track happiness). The natural life is, above all, the rational life, for stoics. |
| 13324 | Living contrary to nature is like rowing against the stream [Seneca] |
| Full Idea: For those who follow nature everything is easy and straightforward, whereas for those who fight against her life is just like rowing against the stream. | |
| From: Seneca the Younger (Letters from a Stoic [c.60], 102) | |
| A reaction: A classic statement of the well-known stoic slogan, but expressed with Seneca's characteristic elegance. There is always a slight hidden of dubious fatalism in the slogan. 'Rage, rage, against the dying of the light!' - Dylan Thomas. |
| 13305 | Character is ruined by not looking back over our pasts, since the future rests on the past [Seneca] |
| Full Idea: What really ruins our characters is the fact that none of us looks back over his life. We think a little about what we are going to do, and fail to think about what we have done, yet plans for the future depend on the past. | |
| From: Seneca the Younger (Letters from a Stoic [c.60], 083) | |
| A reaction: One always assumes that writings about the wisdom of daily life will be one mass of clichés, but Seneca proves otherwise. With a pang I realise that I may be too guilty of not thinking about the past. I've even been proud of it. |
| 7903 | The six perfections are giving, morality, patience, vigour, meditation, and wisdom [Nagarjuna] |
| Full Idea: The six perfections are of giving, morality, patience, vigour, meditation, and wisdom. | |
| From: Nagarjuna (Mahaprajnaparamitashastra [c.120], 88) | |
| A reaction: What is 'morality', if giving is not part of it? I like patience and vigour being two of the virtues, which immediately implies an Aristotelian mean (which is always what is 'appropriate'). |
| 13312 | Excessive curiosity is a form of intemperance [Seneca] |
| Full Idea: To want to know more than is sufficient is a form of intemperance. | |
| From: Seneca the Younger (Letters from a Stoic [c.60], 088) | |
| A reaction: This comes as a bit of a surprise, given the high value that philosophers place on knowledge. I'm reminded of Auberon Waugh's criticism of the Scots as a 'wildly over-educated people'. I think the problem is what you could have been doing instead. |
| 13308 | It's no good winning lots of fights, if you are then conquered by your own temper [Seneca] |
| Full Idea: What's the use of overcoming opponent after opponent in the wrestling or boxing rings if you can be overcome by your temper? | |
| From: Seneca the Younger (Letters from a Stoic [c.60], 088) | |
| A reaction: He has such a nice way of presenting what might be traditional and commonplace ideas. If you see life as a battle, then you should think very carefully about who the opponents are - because they may be hiding within. |
| 13315 | To govern used to mean to serve, not to rule; rulers did not test their powers over those who bestowed it [Seneca] |
| Full Idea: In the Golden Age, to govern was to serve, not to rule. No one used to try out the extent of his power over those to whom he owed that power in the first place. | |
| From: Seneca the Younger (Letters from a Stoic [c.60], 090) | |
| A reaction: I spent my professional career trying to persuade people that management should be a subjection to the managed. Wake up! The second half of this idea is the interesting bit - the temptation to just 'try out' your powers gets to them all. |
| 13290 | One joy of learning is making teaching possible [Seneca] |
| Full Idea: Part of my joy in learning is that it puts me in a position to teach. | |
| From: Seneca the Younger (Letters from a Stoic [c.60], 006) | |
| A reaction: This doesn't quite distinguish between bad learning and good learning, but I take a commitment to wanting to teach what you know as an essential part of wanting to know. |
| 13322 | Both teachers and pupils should aim at one thing - the improvement of the pupil [Seneca] |
| Full Idea: A person teaching and a person learning should have the same end in view: the improvement of the latter. | |
| From: Seneca the Younger (Letters from a Stoic [c.60], 108) | |
| A reaction: [He cites a philospher called Attalus for this remark] This is worthy to be up in the hall of every educational institution in the world, and especially in the staff rooms. |
| 13298 | Suicide may be appropriate even when it is not urgent, if there are few reasons against it [Seneca] |
| Full Idea: There are many occasions on which a man should leave life not only bravely but for reasons which are not as pressing as they might be - the reasons which restrain us being not so pressing either. | |
| From: Seneca the Younger (Letters from a Stoic [c.60], 077) | |
| A reaction: This is an interesting and startling claim from the great champion of suicide, who nobly and memorably committed suicide himself. But we all dread a loved one miscalculating Seneca's dialectic, and dying when living would have been better. |
| 13320 | Sometimes we have a duty not to commit suicide, for those we love [Seneca] |
| Full Idea: There are times when, however pressing one's reasons to the contrary, one's dying breath must be held back as it is passing one's lips, even if this is torture, simply out of consideration for one's dear ones. | |
| From: Seneca the Younger (Letters from a Stoic [c.60], 104) | |
| A reaction: This is, of course, a highly significant counterbalance to his normal acceptance of suicide. I wish anyone who is planning suicide would heed it. They have no idea how much suffering will usually result from their action. |
| 13319 | If we control our own death, no one has power over us [Seneca] |
| Full Idea: No one has power over us when death is in our own power. | |
| From: Seneca the Younger (Letters from a Stoic [c.60], 091) | |
| A reaction: A classic slogan for the stoic view of suicide, an idea that crops up in Shakespeare's 'Julius Caesar'. He doesn't seem to have understood that they can take away your shoelaces. |
| 12375 | Whatever holds of a kind intrinsically holds of it necessarily [Aristotle] |
| Full Idea: In each kind, whatever holds of something in itself and as such holds of it from necessity. | |
| From: Aristotle (Posterior Analytics [c.327 BCE], 75a30) | |
| A reaction: This seems to confirm the view that essential properties are necessary, but it does not, of course, follow that all necessary properties are essential properties (e.g. trivial necessities are not essential). |
| 13311 | Does time exist on its own? Did anything precede it? Did it pre-exist the cosmos? [Seneca] |
| Full Idea: Look how many questions there are on time. Does it have an existence of its own? Does anything exist prior to time, independently of it? Did it begin with the universe, or did it exist even before then? | |
| From: Seneca the Younger (Letters from a Stoic [c.60], 088) | |
| A reaction: I'm not sure that the questions have shifted or become any clearer after two thousand years, despite Einstein and co. Note that discussions of time were not initiated by Augustine. |
| 1688 | Properties must be proved, but not essence; but existents are not a kind, so existence isn't part of essence [Aristotle] |
| Full Idea: Everything which a thing is must be proved through a demonstration - except its essence. But existence is not the essence of anything; for the things that exist do not constitute a kind. | |
| From: Aristotle (Posterior Analytics [c.327 BCE], 92b14) |