21 ideas
| 19740 | A very hungry man cannot choose between equidistant piles of food [Aristotle] |
| Full Idea: The man who, though exceedingly hungry and thirsty, and both equally, yet being equidistant from food and drink, is therefore bound to stay where he is. | |
| From: Aristotle (On the Heavens [c.336 BCE], 296b33) | |
| A reaction: This is, of course, Buridan's famous Ass, but this quotation has the advantage of precedence, and also of being expressed in an original quotation (which does not exist for Buridan). |
| 8361 | What is true used to be possible, but it may no longer be so [Wright,GHv] |
| Full Idea: It is not very natural to say of that which is true that it is also possible. ...What is true was possible - but whether it still is a potency of the world is not certain. | |
| From: G.H. von Wright (Logic and Epistemology of Causal Relations [1973], §5) | |
| A reaction: A simple and rather important distinction. Before encountering this, I would certainly have been happy to affirm that the actual is possible, but actually it may not be. The power to create differs from the power to sustain. Could God re-create the world? |
| 398 | Each thing that has a function is for the sake of that function [Aristotle] |
| Full Idea: Each thing that has a function is for the sake of that function. | |
| From: Aristotle (On the Heavens [c.336 BCE], 286a08) | |
| A reaction: This is the central idea of Aristotle's Ethics. Did it originate with Plato, or Socrates, the young pupil Aristotle? I suspect the strong influence of Aristotle on later Plato. A major idea. Functions link the facts to life. |
| 13304 | Learned men gain more in one day than others do in a lifetime [Posidonius] |
| Full Idea: In a single day there lies open to men of learning more than there ever does to the unenlightened in the longest of lifetimes. | |
| From: Posidonius (fragments/reports [c.95 BCE]), quoted by Seneca the Younger - Letters from a Stoic 078 | |
| A reaction: These remarks endorsing the infinite superiority of the educated to the uneducated seem to have been popular in late antiquity. It tends to be the religions which discourage great learning, especially in their emphasis on a single book. |
| 394 | An unworn sandal is in vain, but nothing in nature is in vain [Aristotle] |
| Full Idea: We say of a sandal which is not worn that it is in vain; God and nature, however, do nothing in vain. | |
| From: Aristotle (On the Heavens [c.336 BCE], 271a33) |
| 396 | There has to be some goal, and not just movement to infinity [Aristotle] |
| Full Idea: There has to be some goal, and not just movement to infinity. | |
| From: Aristotle (On the Heavens [c.336 BCE], 277a26) |
| 16102 | Aether moves in circles and is imperishable; the four elements perish, and move in straight lines [Aristotle, by Gill,ML] |
| Full Idea: For Aristotle, aether and the four sublunary elements obey different physical laws. Aether moves naturally in a circle and, unlike its lower counterparts, is not a source of perishability. The four sublunary elements move naturally in straight lines. | |
| From: report of Aristotle (On the Heavens [c.336 BCE]) by Mary Louise Gill - Aristotle on Substance Ch.2 | |
| A reaction: I think it is anachronistic for Gill to talk of 'obeying' and 'laws'. She should have said that they have different 'natures'. We can be amused by Greek errors, until we stare hard at the problems they were trying to solve. |
| 17463 | An element is what bodies are analysed into, and won't itself divide into something else [Aristotle] |
| Full Idea: An element is a body into which other bodies may be analyzed, present in them potentially or in actuality (which of these is still disputable), and not itself divisible into bodies different in form. That is what all men mean by element. | |
| From: Aristotle (On the Heavens [c.336 BCE], 302a05), quoted by Weisberg/Needham/Hendry - Philosophy of Chemistry 1.1 | |
| A reaction: This is the classic definition of an element, which endured for a long time, and has been replaced by an 'actual components' view. Obviously analysis nowadays goes well beyond the atoms. |
| 8363 | p is a cause and q an effect (not vice versa) if manipulations of p change q [Wright,GHv] |
| Full Idea: What makes p a cause-factor relative to the effect-factor q (rather than vice versa) is the fact that by manipulating p, producing changes in it 'at will', we could bring about changes in q. | |
| From: G.H. von Wright (Logic and Epistemology of Causal Relations [1973], §8) | |
| A reaction: As a solution to the direction-of-causation problem, I suspect that this proposal is begging the question. Will a causal explanation be offered of the action of manipulation? If he mistook his manipulation for a cause when it is actually an effect... |
| 8364 | We can imagine controlling floods by controlling rain, but not vice versa [Wright,GHv] |
| Full Idea: Given our present knowledge of the laws of nature, we can imagine ways of controlling floods by controlling rainfall, but not the other way round. That is should be so, however, is contingent. | |
| From: G.H. von Wright (Logic and Epistemology of Causal Relations [1973], §8) | |
| A reaction: Despite my objections to Idea 8363, this is a good example. It won't establish the metaphysics of the direction of causation, though, because God might control rainfall by controlling floods. Maybe causation is more like a motorway pile-up than dominoes. |
| 8366 | The very notion of a cause depends on agency and action [Wright,GHv] |
| Full Idea: There is an implicit dependence of the very notion of a cause on a concept of agency and action. | |
| From: G.H. von Wright (Logic and Epistemology of Causal Relations [1973], §10) | |
| A reaction: This is because he thinks experimental intervention is the key to the concept of causation (see Ideas 8362 and 8363). Others go further, and say that the concept of causation arises from subjective experience of performing actions. I quite like that. |
| 8362 | We give regularities a causal character by subjecting them to experiment [Wright,GHv] |
| Full Idea: What confers on observed regularities the character of causal or nomic connections is the possibility of subjecting cause-factors to experimental test by interfering with the 'natural' course of events. | |
| From: G.H. von Wright (Logic and Epistemology of Causal Relations [1973], §7) | |
| A reaction: This is von Wright's distinctive proposal, making causation a feature of the culture of science, rather than of ordinary life. But see Idea 2461. Causation is becoming too epistemological for my taste. Either it is a feature of reality, or forget it. |
| 8360 | We must further analyse conditions for causation, into quantifiers or modal concepts [Wright,GHv] |
| Full Idea: We may be able to analyse causation into conditionship relations between events or states of affairs, ...but conditions cannot be regarded as logical primitives, ... and must be analysed into quantifiers, or modal concepts. | |
| From: G.H. von Wright (Logic and Epistemology of Causal Relations [1973], §2) | |
| A reaction: [very compressed] A nice illustration of the aim of analytical philosophy - to analyse the elements of reality down to logical primitives. This is the dream of Descartes and Leibniz, continued by Russell and co. Do we still have this aspiration? |
| 8365 | Some laws are causal (Ohm's Law), but others are conceptual principles (conservation of energy) [Wright,GHv] |
| Full Idea: Not all laws are causal 'experimentalist' laws, such as those for falling bodies, or the Gas Law, or Ohm's Law. Some are more like conceptual principles, giving a frame of reference, such as inertia, or conservation of energy, or the law of entropy. | |
| From: G.H. von Wright (Logic and Epistemology of Causal Relations [1973], §9) | |
| A reaction: An interesting and important distinction, whenever one is exploring the links between theories of causation and of laws of nature. If one wished to attack the whole concept of 'laws of nature', this might be a good place to start. |
| 399 | If the more you raise some earth the faster it moves, why does the whole earth not move? [Aristotle] |
| Full Idea: If you raise some earth and release it, it moves and won't stay put, and the more you raise it the faster it moves, so why does the whole earth not move? | |
| From: Aristotle (On the Heavens [c.336 BCE], 294a12) |
| 20918 | Void is a kind of place, so it can't explain place [Aristotle] |
| Full Idea: It is absurd to explain place by the void, as though this latter were not itself some kind of place. | |
| From: Aristotle (On the Heavens [c.336 BCE], 309b24) | |
| A reaction: Presumably this is aimed at Democritus. |
| 20820 | Time is an interval of motion, or the measure of speed [Posidonius, by Stobaeus] |
| Full Idea: Posidonius defined time thus: it is an interval of motion, or the measure of speed and slowness. | |
| From: report of Posidonius (fragments/reports [c.95 BCE]) by John Stobaeus - Anthology 1.08.42 | |
| A reaction: Hm. Can we define motion or speed without alluding to time? Looks like we have to define them as a conjoined pair, which means we cannot fully understand either of them. |
| 402 | The Earth must be spherical, because it casts a convex shadow on the moon [Aristotle] |
| Full Idea: A lunar eclipse always has a convex dividing line, so, if it is eclipsed by the interposition of the earth, the circumference of the earth, being spherical, is responsible for the shape. | |
| From: Aristotle (On the Heavens [c.336 BCE], 297b29) |
| 403 | The earth must be round and of limited size, because moving north or south makes different stars visible [Aristotle] |
| Full Idea: Clearly the earth is round and not of great size, because when we move north or south we find that very different stars are visible. | |
| From: Aristotle (On the Heavens [c.336 BCE], 297b30) |
| 1498 | Everyone agrees that the world had a beginning, but thinkers disagree over whether it will end [Aristotle] |
| Full Idea: All thinkers agree that the world had a beginning, but some claim that, having come into existence, it is everlasting. | |
| From: Aristotle (On the Heavens [c.336 BCE], 279b12) |
| 395 | It seems possible that there exists a limited number of other worlds apart from this one [Aristotle] |
| Full Idea: One might indeed be puzzled whether, just as the world about us exists, nothing prevents there being others as well, certainly more than one, though not an unlimited number | |
| From: Aristotle (On the Heavens [c.336 BCE], 274a26) |