123 ideas
| 11283 | There is pure deductive reasoning, and explanatory demonstration reasoning [Aristotle, by Politis] |
| 1672 | Maybe everything could be demonstrated, if demonstration can be reciprocal or circular [Aristotle] |
| 1684 | Two falsehoods can be contrary to one another [Aristotle] |
| 12145 | Definitions are of what something is, and that is universal [Aristotle] |
| 12075 | An Aristotelian definition is causal [Aristotle, by Witt] |
| 12384 | Definition by division needs predicates, which are well ordered and thorough [Aristotle] |
| 9066 | You can define objects by progressively identifying what is the same and what is different [Aristotle] |
| 12382 | What it is and why it is are the same; screening defines and explains an eclipse [Aristotle] |
| 5728 | The concept of truth was originated by the senses [Lucretius] |
| 1668 | An axiom is a principle which must be understood if one is to learn anything [Aristotle] |
| 12376 | Demonstrations by reductio assume excluded middle [Aristotle] |
| 12373 | Something holds universally when it is proved of an arbitrary and primitive case [Aristotle] |
| 12363 | Everything is either asserted or denied truly [Aristotle] |
| 4975 | A thought can be split in many ways, so that different parts appear as subject or predicate [Frege] |
| 13004 | Aristotle's axioms (unlike Euclid's) are assumptions awaiting proof [Aristotle, by Leibniz] |
| 12377 | Mathematics is concerned with forms, not with superficial properties [Aristotle] |
| 12372 | The essence of a triangle comes from the line, mentioned in any account of triangles [Aristotle] |
| 12369 | A unit is what is quantitatively indivisible [Aristotle] |
| 9949 | There is the concept, the object falling under it, and the extension (a set, which is also an object) [Frege, by George/Velleman] |
| 18995 | Frege mistakenly takes existence to be a property of concepts, instead of being about things [Frege, by Yablo] |
| 18910 | To seek truth, study the real connections between subjects and attributes [Aristotle] |
| 10317 | It is unclear whether Frege included qualities among his abstract objects [Frege, by Hale] |
| 1675 | Separate Forms aren't needed for logic, but universals (one holding of many) are essential [Aristotle] |
| 1677 | We can forget the Forms, as they are irrelevant, and not needed in giving demonstrations [Aristotle] |
| 10535 | Frege's 'objects' are both the referents of proper names, and what predicates are true or false of [Frege, by Dummett] |
| 1687 | Why are being terrestrial and a biped combined in the definition of man, but being literate and musical aren't? [Aristotle] |
| 1681 | Units are positionless substances, and points are substances with position [Aristotle] |
| 12146 | Definitions recognise essences, so are not themselves essences [Aristotle] |
| 17039 | The predicates of a thing's nature are necessary to it [Aristotle] |
| 11994 | Aristotelian essences are properties mentioned at the starting point of a science [Aristotle, by Kung] |
| 12381 | What is necessary cannot be otherwise [Aristotle] |
| 1690 | A stone travels upwards by a forced necessity, and downwards by natural necessity [Aristotle] |
| 12072 | For Aristotle knowledge is explanatory, involving understanding, and principles or causes [Aristotle, by Witt] |
| 12073 | 'Episteme' means grasping causes, universal judgments, explanation, and teaching [Aristotle, by Witt] |
| 12378 | The reason why is the key to knowledge [Aristotle] |
| 12364 | We understand a thing when we know its explanation and its necessity [Aristotle] |
| 12366 | We only understand something when we know its explanation [Aristotle] |
| 12370 | Some understanding, of immediate items, is indemonstrable [Aristotle] |
| 1685 | No one has mere belief about something if they think it HAS to be true [Aristotle] |
| 1673 | Knowledge proceeds from principles, so it is hard to know if we know [Aristotle] |
| 12379 | You cannot understand anything through perception [Aristotle] |
| 16725 | Some knowledge is lost if you lose a sense, and there is no way the knowledge can be replaced [Aristotle] |
| 5729 | If the senses are deceptive, reason, which rests on them, is even worse [Lucretius] |
| 5702 | The senses are much the best way to distinguish true from false [Lucretius] |
| 23309 | Aristotle's concepts of understanding and explanation mean he is not a pure empiricist [Aristotle, by Frede,M] |
| 1693 | Animals may have some knowledge if they retain perception, but understanding requires reasons to be given [Aristotle] |
| 9067 | Many memories of the same item form a single experience [Aristotle] |
| 1671 | Sceptics say justification is an infinite regress, or it stops at the unknowable [Aristotle] |
| 1670 | When you understand basics, you can't be persuaded to change your mind [Aristotle] |
| 5697 | The only possible standard for settling doubts is the foundation of the senses [Lucretius] |
| 5727 | Most supposed delusions of the senses are really misinterpretations by the mind [Lucretius] |
| 1674 | All demonstration is concerned with existence, axioms and properties [Aristotle] |
| 24068 | Demonstration is more than entailment, as the explanatory order must match the causal order [Aristotle, by Koslicki] |
| 17310 | Aristotle gets asymmetric consequence from demonstration, which reflects real causal priority [Aristotle, by Koslicki] |
| 21359 | Aristotle doesn't actually apply his theory of demonstration to his practical science [Leroi on Aristotle] |
| 1667 | Premises must be true, primitive and immediate, and prior to and explanatory of conclusions [Aristotle] |
| 12365 | We can know by demonstration, which is a scientific deduction leading to understanding [Aristotle] |
| 10918 | Demonstrative understanding rests on necessary features of the thing in itself [Aristotle] |
| 12374 | Demonstrations must be necessary, and that depends on the middle term [Aristotle] |
| 12148 | Demonstrations are syllogisms which give explanations [Aristotle] |
| 1679 | Universal demonstrations are about thought; particular demonstrations lead to perceptions [Aristotle] |
| 1680 | Demonstration is better with fewer presuppositions, and it is quicker if these are familiar [Aristotle] |
| 1691 | Aim to get definitions of the primitive components, thus establishing the kind, and work towards the attributes [Aristotle] |
| 12383 | There must be definitions before demonstration is possible [Aristotle] |
| 12147 | The principles of demonstrations are definitions [Aristotle] |
| 12371 | A demonstration is a deduction which proceeds from necessities [Aristotle] |
| 5714 | Even simple facts are hard to believe at first hearing [Lucretius] |
| 1683 | We learn universals from many particulars [Aristotle] |
| 12385 | Are particulars explained more by universals, or by other particulars? [Aristotle] |
| 12380 | Universals are valuable because they make the explanations plain [Aristotle] |
| 12367 | What is most universal is furthest away, and the particulars are nearest [Aristotle] |
| 1686 | What we seek and understand are facts, reasons, existence, and identity [Aristotle] |
| 1689 | Explanation is of the status of a thing, inferences to it, initiation of change, and purpose [Aristotle] |
| 12357 | Explanation and generality are inseparable [Aristotle, by Wedin] |
| 1669 | The foundation or source is stronger than the thing it causes [Aristotle] |
| 1678 | Universals give better explanations, because they are self-explanatory and primitive [Aristotle] |
| 5718 | The mind is in the middle of the breast, because there we experience fear and joy [Lucretius] |
| 5717 | The mind is a part of a man, just like a hand or an eye [Lucretius] |
| 21387 | The separate elements and capacities of a mind cannot be distinguished [Lucretius] |
| 9068 | Perception creates primitive immediate principles by building a series of firm concepts [Aristotle] |
| 9069 | A perception lodging in the soul creates a primitive universal, which becomes generalised [Aristotle] |
| 5709 | The actions of the mind are not determinate and passive, because atoms can swerve [Lucretius] |
| 5695 | Only bodies can touch one another [Lucretius] |
| 5711 | The earth is and always has been an insentient being [Lucretius] |
| 5712 | Particles may have sensation, but eggs turning into chicks suggests otherwise [Lucretius] |
| 5719 | The mind moves limbs, wakes the body up, changes facial expressions, which involve touch [Lucretius] |
| 5724 | Lions, foxes and deer have distinct characters because their minds share in their bodies [Lucretius] |
| 5713 | You needn't be made of laughing particles to laugh, so why not sensation from senseless seeds? [Lucretius] |
| 9839 | Frege equated the concepts under which an object falls with its properties [Frege, by Dummett] |
| 4973 | As I understand it, a concept is the meaning of a grammatical predicate [Frege] |
| 9070 | We learn primitives and universals by induction from perceptions [Aristotle] |
| 9167 | Frege felt that meanings must be public, so they are abstractions rather than mental entities [Frege, by Putnam] |
| 4974 | For all the multiplicity of languages, mankind has a common stock of thoughts [Frege] |
| 12368 | Negation takes something away from something [Aristotle] |
| 1692 | If you shouldn't argue in metaphors, then you shouldn't try to define them either [Aristotle] |
| 6611 | One man's meat is another man's poison [Lucretius] |
| 5730 | Our bodies weren't created to be used; on the contrary, their creation makes a use possible [Lucretius] |
| 5726 | The dead are no different from those who were never born [Lucretius] |
| 5705 | Nature only wants two things: freedom from pain, and pleasure [Lucretius] |
| 5716 | Nature runs the universe by herself without the aid of gods [Lucretius] |
| 5704 | There can be no centre in infinity [Lucretius] |
| 5703 | The universe must be limitless, since there could be nothing outside to limit it [Lucretius] |
| 5693 | Everything is created and fed by nature from atoms, and they return to atoms in death [Lucretius] |
| 5701 | If an object is infinitely subdivisible, it will be the same as the whole universe [Lucretius] |
| 5708 | In downward motion, atoms occasionally swerve slightly for no reason [Lucretius] |
| 12375 | Whatever holds of a kind intrinsically holds of it necessarily [Aristotle] |
| 17004 | Nothing can break the binding laws of eternity [Lucretius] |
| 5696 | If there were no space there could be no movement, or even creation [Lucretius] |
| 5706 | Atoms move themselves [Lucretius] |
| 5700 | It is quicker to break things up than to assemble them [Lucretius] |
| 5698 | We can only sense time by means of movement, or its absence [Lucretius] |
| 5715 | This earth is very unlikely to be the only one created [Lucretius] |
| 5694 | Nothing can be created by divine power out of nothing [Lucretius] |
| 1688 | Properties must be proved, but not essence; but existents are not a kind, so existence isn't part of essence [Aristotle] |
| 5699 | If matter wasn't everlasting, everything would have disappeared by now [Lucretius] |
| 5707 | The universe can't have been created by gods, because it is too imperfect [Lucretius] |
| 5710 | Gods are tranquil and aloof, and have no need of or interest in us [Lucretius] |
| 5731 | Why does Jupiter never hurl lightning from a blue sky? [Lucretius] |
| 5720 | Spirit is mortal [Lucretius] |
| 5722 | For a separated spirit to remain sentient it would need sense organs attached to it [Lucretius] |
| 5725 | An immortal mind couldn't work harmoniously with a mortal body [Lucretius] |
| 5721 | The mind is very small smooth particles, which evaporate at death [Lucretius] |
| 5723 | If spirit is immortal and enters us at birth, why don't we remember a previous existence? [Lucretius] |