18 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). |
14637 | Only individuals have essences, so numbers (as a higher type based on classes) lack them [McMichael] |
Full Idea: Essentialism is not verified by the observation that numbers have interesting essential properties, since they are properties of classes and so are entities of a higher logical type than individuals. | |
From: Alan McMichael (The Epistemology of Essentialist Claims [1986], Intro) | |
A reaction: This relies on a particular view of number (which might be challenged), but is interesting when it comes to abstract entities having essences. Only ur-elements in set theory could have essences, it seems. Why? Rising in type destroys essence? |
14636 | Essences are the interesting necessary properties resulting from a thing's own peculiar nature [McMichael] |
Full Idea: Essentialism says some individuals have certain 'interesting' necessary properties. If it exists, it has that property. The properties are 'interesting' as had in virtue of their own peculiar natures, rather than as general necessary truths. | |
From: Alan McMichael (The Epistemology of Essentialist Claims [1986], Intro) | |
A reaction: [compressed] This is a modern commentator caught between two views. The idea that essence is the non-trivial-necessary properties is standard, but adding their 'peculiar natures' connects him to Aristotle, and Kit Fine's later papers. Good! |
14640 | Maybe essential properties have to be intrinsic, as well as necessary? [McMichael] |
Full Idea: There is a tendency to think of essential properties as having some characteristic in addition to their necessity, such as intrinsicality. | |
From: Alan McMichael (The Epistemology of Essentialist Claims [1986], VIII) | |
A reaction: Personally I am inclined to take this view of all properties, and not just the 'essential' ones. General necessities, relations, categorisations, disjunctions etc. should not be called 'properties', even if they are 'predicates'. Huge confusion results. |
14638 | Essentialism is false, because it implies the existence of necessary singular propositions [McMichael] |
Full Idea: Essentialism entails the existence of necessary singular propositions that are not instances of necessary generalizations. Therefore, since there are no such propositions, essentialism is false. | |
From: Alan McMichael (The Epistemology of Essentialist Claims [1986], I) | |
A reaction: This summarises the attack which McMichael wishes to deal with. I am wickedly tempted to say that essences actually have a contingent existence (or a merely hypothetical dependent necessity), and this objection might be grist for my mill. |
6017 | Nomos is king [Pindar] |
Full Idea: Nomos is king. | |
From: Pindar (poems [c.478 BCE], S 169), quoted by Thomas Nagel - The Philosophical Culture | |
A reaction: This seems to be the earliest recorded shot in the nomos-physis wars (the debate among sophists about moral relativism). It sounds as if it carries the full relativist burden - that all that matters is what has been locally decreed. |
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. |
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. |
14639 | Individuals enter into laws only through their general qualities and relations [McMichael] |
Full Idea: Individuals appear to enter into laws only through their general qualities and relations. | |
From: Alan McMichael (The Epistemology of Essentialist Claims [1986], VIII) | |
A reaction: This is a very significant chicken-or-egg issue. The remark seems to offer the vision of pre-existing general laws, which individuals then join (like joining a club). But surely the laws are derived from the individuals? Where else could they come from? |
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. |
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) |
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) |
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) |