130 ideas
291 | Don't assume that wisdom is the automatic consequence of old age [Plato] |
17016 | Philosophy must abstract from the senses [Newton] |
5361 | Philosophers must get used to absurdities [Russell] |
5368 | Philosophy verifies that our hierarchy of instinctive beliefs is harmonious and consistent [Russell] |
5432 | Metaphysics cannot give knowledge of the universe as a whole [Russell] |
5434 | Philosophy is similar to science, and has no special source of wisdom [Russell] |
5396 | Three Laws of Thought: identity, contradiction, and excluded middle [Russell] |
5405 | The law of contradiction is not a 'law of thought', but a belief about things [Russell] |
5420 | Truth is a property of a belief, but dependent on its external relations, not its internal qualities [Russell] |
5419 | Truth and falsehood are properties of beliefs and statements [Russell] |
5417 | A good theory of truth must make falsehood possible [Russell] |
7395 | Truth as congruence may work for complex beliefs, but not for simple beliefs about existence [Joslin on Russell] |
5428 | Beliefs are true if they have corresponding facts, and false if they don't [Russell] |
5421 | The coherence theory says falsehood is failure to cohere, and truth is fitting into a complete system of Truth [Russell] |
5422 | More than one coherent body of beliefs seems possible [Russell] |
5423 | If we suspend the law of contradiction, nothing will appear to be incoherent [Russell] |
5424 | Coherence is not the meaning of truth, but an important test for truth [Russell] |
5401 | The mortality of Socrates is more certain from induction than it is from deduction [Russell] |
5395 | Demonstration always relies on the rule that anything implied by a truth is true [Russell] |
5386 | Proper names are really descriptions, and can be replaced by a description in a person's mind [Russell] |
5385 | The phrase 'a so-and-so' is an 'ambiguous' description'; 'the so-and-so' (singular) is a 'definite' description [Russell] |
18079 | Newton developed a kinematic approach to geometry [Newton, by Kitcher] |
18082 | Quantities and ratios which continually converge will eventually become equal [Newton] |
5399 | Maths is not known by induction, because further instances are not needed to support it [Russell] |
5370 | Space is neutral between touch and sight, so it cannot really be either of them [Russell] |
5418 | In a world of mere matter there might be 'facts', but no truths [Russell] |
5371 | Because we depend on correspondence, we know relations better than we know the items that relate [Russell] |
5407 | That Edinburgh is north of London is a non-mental fact, so relations are independent universals [Russell] |
17011 | I suspect that each particle of bodies has attractive or repelling forces [Newton] |
5383 | Every complete sentence must contain at least one word (a verb) which stands for a universal [Russell] |
4428 | Propositions express relations (prepositions and verbs) as well as properties (nouns and adjectives) [Russell] |
5406 | Confused views of reality result from thinking that only nouns and adjectives represent universals [Russell] |
4479 | All universals are like the relation "is north of", in having no physical location at all [Russell, by Loux] |
4427 | Every sentence contains at least one word denoting a universal, so we need universals to know truth [Russell] |
4030 | Russell claims that universals are needed to explain a priori knowledge (as their relations) [Russell, by Mellor/Oliver] |
5409 | Normal existence is in time, so we must say that universals 'subsist' [Russell] |
5408 | If we identify whiteness with a thought, we can never think of it twice; whiteness is the object of a thought [Russell] |
4441 | 'Resemblance Nominalism' won't work, because the theory treats resemblance itself as a universal [Russell] |
4429 | If we consider whiteness to be merely a mental 'idea', we rob it of its universality [Russell] |
17028 | Particles mutually attract, and cohere at short distances [Newton] |
17014 | The place of a thing is the sum of the places of its parts [Newton] |
5400 | In any possible world we feel that two and two would be four [Russell] |
5431 | Knowledge cannot be precisely defined, as it merges into 'probable opinion' [Russell] |
5426 | Belief relates a mind to several things other than itself [Russell] |
5366 | We have an 'instinctive' belief in the external world, prior to all reflection [Russell] |
5359 | Descartes showed that subjective things are the most certain [Russell] |
5377 | 'Acquaintance' is direct awareness, without inferences or judgements [Russell] |
6510 | Russell (1912) said phenomena only resemble reality in abstract structure [Russell, by Robinson,H] |
5372 | There is no reason to think that objects have colours [Russell] |
5373 | 'Idealism' says that everything which exists is in some sense mental [Russell] |
5362 | It is not illogical to think that only myself and my mental events exist [Russell] |
5412 | Some propositions are self-evident, but their implications may also be self-evident [Russell] |
5413 | Particular instances are more clearly self-evident than any general principles [Russell] |
5415 | As shown by memory, self-evidence comes in degrees [Russell] |
5416 | If self-evidence has degrees, we should accept the more self-evident as correct [Russell] |
5397 | The rationalists were right, because we know logical principles without experience [Russell] |
4430 | All a priori knowledge deals with the relations of universals [Russell] |
5411 | We can know some general propositions by universals, when no instance can be given [Russell] |
6514 | Russell's representationalism says primary qualities only show the structure of reality [Russell, by Robinson,H] |
6415 | After 1912, Russell said sense-data are last in analysis, not first in experience [Russell, by Grayling] |
5358 | 'Sense-data' are what are immediately known in sensation, such as colours or roughnesses [Russell] |
7290 | If Russell rejects innate ideas and direct a priori knowledge, he is left with a tabula rasa [Russell, by Thompson] |
5357 | It is natural to begin from experience, and presumably that is the basis of knowledge [Russell] |
5382 | We are acquainted with outer and inner sensation, memory, Self, and universals [Russell, by PG] |
5389 | Knowledge by descriptions enables us to transcend private experience [Russell] |
5376 | I can know the existence of something with which nobody is acquainted [Russell] |
5414 | Images are not memory, because they are present, and memories are of the past [Russell] |
5430 | A true belief is not knowledge if it is reached by bad reasoning [Russell] |
5429 | True belief is not knowledge when it is deduced from false belief [Russell] |
5378 | All knowledge (of things and of truths) rests on the foundations of acquaintance [Russell] |
5365 | Dreams can be explained fairly scientifically if we assume a physical world [Russell] |
5391 | Science aims to find uniformities to which (within the limits of experience) there are no exceptions [Russell] |
17546 | If you changed one of Newton's concepts you would destroy his whole system [Heisenberg on Newton] |
17027 | Science deduces propositions from phenomena, and generalises them by induction [Newton] |
5394 | We can't prove induction from experience without begging the question [Russell] |
5390 | Chickens are not very good at induction, and are surprised when their feeder wrings their neck [Russell] |
5392 | It doesn't follow that because the future has always resembled the past, that it always will [Russell] |
17022 | We should admit only enough causes to explain a phenomenon, and no more [Newton] |
17021 | Natural effects of the same kind should be assumed to have the same causes [Newton] |
17026 | From the phenomena, I can't deduce the reason for the properties of gravity [Newton] |
5363 | If the cat reappears in a new position, presumably it has passed through the intermediate positions [Russell] |
5367 | Belief in real objects makes our account of experience simpler and more systematic [Russell] |
5364 | It is hard not to believe that speaking humans are expressing thoughts, just as we do ourselves [Russell] |
5379 | If we didn't know our own minds by introspection, we couldn't know that other people have minds [Russell] |
5410 | I learn the universal 'resemblance' by seeing two shades of green, and their contrast with red [Russell] |
5381 | In seeing the sun, we are acquainted with our self, but not as a permanent person [Russell] |
5380 | In perceiving the sun, I am aware of sun sense-data, and of the perceiver of the data [Russell] |
5369 | It is rational to believe in reality, despite the lack of demonstrative reasons for it [Russell] |
5375 | Knowledge of truths applies to judgements; knowledge by acquaintance applies to sensations and things [Russell] |
21711 | Russell's 'multiple relations' theory says beliefs attach to ingredients, not to propositions [Russell, by Linsky,B] |
5427 | Truth is when a mental state corresponds to a complex unity of external constituents [Russell] |
5425 | In order to explain falsehood, a belief must involve several terms, not two [Russell] |
5384 | A universal of which we are aware is called a 'concept' [Russell] |
13468 | Russell started philosophy of language, by declaring some plausible sentences to be meaningless [Russell, by Hart,WD] |
5388 | Every understood proposition is composed of constituents with which we are acquainted [Russell] |
5387 | It is pure chance which descriptions in a person's mind make a name apply to an individual [Russell] |
21724 | The main aim of the multiple relations theory of judgement was to dispense with propositions [Russell, by Linsky,B] |
293 | Being unafraid (perhaps through ignorance) and being brave are two different things [Plato] |
5398 | Judgements of usefulness depend on judgements of value [Russell] |
6421 | Newton's four fundamentals are: space, time, matter and force [Newton, by Russell] |
13470 | Mass is central to matter [Newton, by Hart,WD] |
17020 | An attraction of a body is the sum of the forces of their particles [Newton] |
23012 | Newtonian causation is changes of motion resulting from collisions [Newton, by Baron/Miller] |
17008 | You have discovered that elliptical orbits result just from gravitation and planetary movement [Newton, by Leibniz] |
17010 | We have given up substantial forms, and now aim for mathematical laws [Newton] |
17023 | I am not saying gravity is essential to bodies [Newton] |
5393 | We can't know that our laws are exceptionless, or even that there are any laws [Russell] |
15866 | Newton reclassified vertical motion as violent, and unconstrained horizontal motion as natural [Newton, by Harré] |
15958 | Inertia rejects the Aristotelian idea of things having natural states, to which they return [Newton, by Alexander,P] |
17017 | 1: Bodies rest, or move in straight lines, unless acted on by forces [Newton] |
17019 | 3: All actions of bodies have an equal and opposite reaction [Newton] |
20968 | Newton's Third Law implies the conservation of momentum [Newton, by Papineau] |
17018 | 2: Change of motion is proportional to the force [Newton] |
17547 | Newton's idea of force acting over a long distance was very strange [Heisenberg on Newton] |
20966 | Newton introduced forces other than by contact [Newton, by Papineau] |
20967 | Newton's laws cover the effects of forces, but not their causes [Newton, by Papineau] |
16708 | Newton's forces were accused of being the scholastics' real qualities [Pasnau on Newton] |
13153 | I am studying the quantities and mathematics of forces, not their species or qualities [Newton] |
12724 | The aim is to discover forces from motions, and use forces to demonstrate other phenomena [Newton] |
13593 | Newton showed that falling to earth and orbiting the sun are essentially the same [Newton, by Ellis] |
20969 | Early Newtonians could not formulate conservation of energy, having no concept of potential energy [Newton, by Papineau] |
17013 | Absolute space is independent, homogeneous and immovable [Newton] |
22915 | Newton needs intervals of time, to define velocity and acceleration [Newton, by Le Poidevin] |
22893 | Newton thought his laws of motion needed absolute time [Newton, by Bardon] |
17012 | Time exists independently, and flows uniformly [Newton] |
14012 | Absolute time, from its own nature, flows equably, without relation to anything external [Newton] |
22954 | Newtonian mechanics does not distinguish negative from positive values of time [Newton, by Coveney/Highfield] |
17015 | If there is no uniform motion, we cannot exactly measure time [Newton] |
17025 | If a perfect being does not rule the cosmos, it is not God [Newton] |
17024 | The elegance of the solar system requires a powerful intellect as designer [Newton] |