28 ideas
| 1798 | He studied philosophy by suspending his judgement on everything [Pyrrho, by Diog. Laertius] |
| Full Idea: He studied philosophy on the principle of suspending his judgement on all points. | |
| From: report of Pyrrho (reports [c.325 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 09.Py.3 | |
| A reaction: In what sense was Pyrrho a philosopher, then? He must have asserted SOME generalised judgments. |
| 1800 | Sceptics say reason is only an instrument, because reason can only be attacked with reason [Pyrrho, by Diog. Laertius] |
| Full Idea: The Sceptics say that they only employ reason as an instrument, because it is impossible to overturn the authority of reason, without employing reason. | |
| From: report of Pyrrho (reports [c.325 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 09.Py.8 |
| 7548 | Classes, grouped by a convenient property, are logical constructions [Russell] |
| Full Idea: Classes or series of particulars, collected together on account of some property which makes it convenient to be able to speak of them as wholes, are what I call logical constructions or symbolic fictions. | |
| From: Bertrand Russell (The Ultimate Constituents of Matter [1915], p.125) | |
| A reaction: When does a construction become 'logical' instead of arbitrary? What is it about a property that makes it 'convenient'? At this point Russell seems to have built his ontology on classes, and the edifice was crumbling, thanks to Wittgenstein. |
| 7545 | Visible things are physical and external, but only exist when viewed [Russell] |
| Full Idea: I believe that common sense is right in regarding what we see as physical and (in one of several possible senses) outside the mind, but is probably wrong in supposing that it continues to exist when we are no longer looking at it. | |
| From: Bertrand Russell (The Ultimate Constituents of Matter [1915], p.123) | |
| A reaction: This remark (in 1915) is a bit startling from a philosopher well known for his robustly realist stance. Just one of his phases! It seems very counterintuitive - that objects really exist externally, but only when viewed. Schrödinger's Cat? |
| 2614 | Modern phenomenalism holds that objects are logical constructions out of sense-data [Ayer] |
| Full Idea: Nowadays phenomenalism is held to be a theory of perception which says that physical objects are logical constructions out of sense-data. | |
| From: A.J. Ayer (Phenomenalism [1947], §1) |
| 2615 | The concept of sense-data allows us to discuss appearances without worrying about reality [Ayer] |
| Full Idea: The introduction of the term 'sense-datum' is a means of referring to appearances without prejudging the question of what it is, if anything, that they are appearances of. | |
| From: A.J. Ayer (Phenomenalism [1947], §1) |
| 7549 | If my body literally lost its mind, the object seen when I see a flash would still exist [Russell] |
| Full Idea: My meaning may be made plainer by saying that if my body could remain in exactly the same state in which it is, though my mind had ceased to exist, precisely that object which I now see when I see a flash would exist, though I should not see it. | |
| From: Bertrand Russell (The Ultimate Constituents of Matter [1915], p.126) | |
| A reaction: Zombies, 70 years before Robert Kirk! Sense-data are physical. It is interesting to see a philosopher as committed to empiricism, anti-spiritualism and the priority of science as this, still presenting an essentially dualist picture of perception. |
| 7553 | Sense-data are purely physical [Russell] |
| Full Idea: Sense-data are purely physical, and all that is mental in connection with them is our awareness of them. | |
| From: Bertrand Russell (The Ultimate Constituents of Matter [1915], p.138) | |
| A reaction: Once this account of sense-data becomes fully clear, it also becomes apparent what a dualist theory it is. The mind is a cinema, I am the audience, and sense-data are the screen. There has to be a big logical gap between viewer and screen. |
| 6595 | If we need a criterion of truth, we need to know whether it is the correct criterion [Pyrrho, by Fogelin] |
| Full Idea: Against the Stoics, the Pyrrhonians argued that if someone presents a criterion of truth, then it will be important to determine whether it is the correct criterion. | |
| From: report of Pyrrho (reports [c.325 BCE]) by Robert Fogelin - Walking the Tightrope of Reason Ch.4 | |
| A reaction: Hence Davidson says that attempts to define truth are 'folly'. If something has to be taken as basic, then truth seems a good candidate (since, for example, logical operators could not otherwise be defined by means of 'truth' tables). |
| 6593 | The Pyrrhonians attacked the dogmas of professors, not ordinary people [Pyrrho, by Fogelin] |
| Full Idea: The attacks of the Pyrrhonian sceptics are directed against the dogmas of the 'professors', not against the beliefs of the common people pursuing the business of daily life. | |
| From: report of Pyrrho (reports [c.325 BCE]) by Robert Fogelin - Walking the Tightrope of Reason Ch.4 | |
| A reaction: This may be because they thought that ordinary people were too confused to be worth attacking, rather than because they lived in a state of beautifully appropriate beliefs. Naïve realism is certainly worth attacking. |
| 6592 | Academics said that Pyrrhonians were guilty of 'negative dogmatism' [Pyrrho, by Fogelin] |
| Full Idea: The ancient Academic sceptics charged the Pyrrhonian sceptics with 'negative dogmatism' when they claimed that a certain kind of knowledge is impossible. | |
| From: report of Pyrrho (reports [c.325 BCE]) by Robert Fogelin - Walking the Tightrope of Reason Ch.4 | |
| A reaction: It is this kind of point which should push us towards some sort of rationalism, because certain a priori 'dogmas' seem to be indispensable to get any sort of discussion off the ground. The only safe person is Cratylus (see Idea 578). |
| 1805 | Judgements vary according to local culture and law (Mode 5) [Pyrrho, by Diog. Laertius] |
| Full Idea: Fifth mode: judgements vary according to local custom, law and culture (Persians marry their daughters). | |
| From: report of Pyrrho (reports [c.325 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 09.Py.9 |
| 1801 | Animals vary in their feelings and judgements (Mode 1) [Pyrrho, by Diog. Laertius] |
| Full Idea: First mode: animals vary in their feelings and judgements (of food, for example). | |
| From: report of Pyrrho (reports [c.325 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 09.Py.9 |
| 1804 | Perception varies with madness or disease (Mode 4) [Pyrrho, by Diog. Laertius] |
| Full Idea: Fourth mode: perceivers vary in their mental and physical state (such as the mad and the sick). | |
| From: report of Pyrrho (reports [c.325 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 09.Py.9 |
| 1808 | Perception of things depends on their size or quantity (Mode 8) [Pyrrho, by Diog. Laertius] |
| Full Idea: Eighth mode: perceptions of things depend on their magnitude or quantity (food and wine). | |
| From: report of Pyrrho (reports [c.325 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 09.Py.9 |
| 1806 | Perception of objects depends on surrounding conditions (Mode 6) [Pyrrho, by Diog. Laertius] |
| Full Idea: Sixth mode: the perception of an object depends on surrounding conditions (sunlight and lamplight). | |
| From: report of Pyrrho (reports [c.325 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 09.Py.9 |
| 1809 | Perception is affected by expectations (Mode 9) [Pyrrho, by Diog. Laertius] |
| Full Idea: Ninth mode: we perceive things according to what we expect (earthquakes and sunshine). | |
| From: report of Pyrrho (reports [c.325 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 09.Py.9 |
| 1803 | Objects vary according to which sense perceives them (Mode 3) [Pyrrho, by Diog. Laertius] |
| Full Idea: Third mode: things like an apple vary according to which sense perceives them (yellow, sweet, and fragrant). | |
| From: report of Pyrrho (reports [c.325 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 09.Py.9 |
| 1807 | Perception varies with viewing distance and angle (Mode 7) [Pyrrho, by Diog. Laertius] |
| Full Idea: Seventh mode: perception varies according to viewing distance and angle (the sun, and a dove's neck). | |
| From: report of Pyrrho (reports [c.325 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 09.Py.9 |
| 1810 | Perception and judgement depend on comparison (Mode 10) [Pyrrho, by Diog. Laertius] |
| Full Idea: Tenth mode: perceptions and judgements depend on comparison (light/heavy, above/below). | |
| From: report of Pyrrho (reports [c.325 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 09.Py.9 |
| 1802 | Individuals vary in responses and feelings (Mode 2) [Pyrrho, by Diog. Laertius] |
| Full Idea: Second mode: individual men vary in responses and feelings (heat and cold, for example). | |
| From: report of Pyrrho (reports [c.325 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 09.Py.9 |
| 7546 | A man is a succession of momentary men, bound by continuity and causation [Russell] |
| Full Idea: The real man, I believe, however the police may swear to his identity, is really a series of momentary men, each different one from the other, and bound together, not by a numerical identity, but by continuity and certain instrinsic causal laws. | |
| From: Bertrand Russell (The Ultimate Constituents of Matter [1915], p.124) | |
| A reaction: This seems to be in the tradition of Locke and Parfit, and also follows the temporal-slices idea of physical objects. Personally I take a more physical view of things, and think the police are probably more reliable than Bertrand Russell. |
| 7550 | We could probably, in principle, infer minds from brains, and brains from minds [Russell] |
| Full Idea: It seems not improbable that if we had sufficient knowledge we could infer the state of a man's mind from the state of his brain, or the state of his brain from the state of his mind. | |
| From: Bertrand Russell (The Ultimate Constituents of Matter [1915], p.131) | |
| A reaction: This strikes me as being a very good summary of the claim that mind is reducible to brain, which is the essence of physicalism. Had he been born a little later, Russell would have taken a harder line with physicalism. |
| 3062 | There are no causes, because they are relative, and alike things can't cause one another [Pyrrho, by Diog. Laertius] |
| Full Idea: The idea of cause is relative to that of which it is the cause, and so has no real existence. …Also cause must either be body causing body, or incorporeal causing incorporeal, and neither of these is possible. | |
| From: report of Pyrrho (reports [c.325 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 09.11.11 |
| 3063 | Motion can't move where it is, and can't move where it isn't, so it can't exist [Pyrrho, by Diog. Laertius] |
| Full Idea: Motion is not moved in the place in which it is is, and it is impossible that it should be moved in the place in which it is not, so there is no such thing as motion. | |
| From: report of Pyrrho (reports [c.325 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 09.11.11 |
| 7551 | Matter is a logical construction [Russell] |
| Full Idea: We must regard matter as a logical construction. | |
| From: Bertrand Russell (The Ultimate Constituents of Matter [1915], p.132) | |
| A reaction: A logical construction is a fancy way of saying a best explanation (but with Ockham's Razor hanging over it). A key component missing from Russell's account is that we can directly experience matter, because we are made of it. |
| 7547 | Matter requires a division into time-corpuscles as well as space-corpuscles [Russell] |
| Full Idea: A true theory of matter requires a division of things into time-corpuscles as well as space-corpuscles. | |
| From: Bertrand Russell (The Ultimate Constituents of Matter [1915], p.125) | |
| A reaction: The division of matter in space seems decidable by physicists, but the division in time seems a bit arbitrary (unless it is quanta of time?). Russell focuses on observable qualities, but are there also intrinsic qualities? |
| 7552 | Six dimensions are needed for a particular, three within its own space, and three to locate that space [Russell] |
| Full Idea: The world of particulars is a six-dimensional space, where six co-ordinates will be required to assign the position of any particular, three to assign its position in its own space, and three to assign the position of its space among the other spaces. | |
| From: Bertrand Russell (The Ultimate Constituents of Matter [1915], p.134) | |
| A reaction: Not a proposal that has caught on. One might connect the idea with the notion of 'frames of reference' in Einstein's Special Theory. Inside a frame of reference, three co-ordinates are needed; but where is the frame of reference? |