7 ideas
| 13007 | Archimedes defined a straight line as the shortest distance between two points [Archimedes, by Leibniz] |
| Full Idea: Archimedes gave a sort of definition of 'straight line' when he said it is the shortest line between two points. | |
| From: report of Archimedes (fragments/reports [c.240 BCE]) by Gottfried Leibniz - New Essays on Human Understanding 4.13 | |
| A reaction: Commentators observe that this reduces the purity of the original Euclidean axioms, because it involves distance and measurement, which are absent from the purest geometry. |
| 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. |
| 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? |
| 15194 | Time, as it appears in standard modern science, is bad verificationist metaphysics [Smith,Q, by Le Poidevin] |
| Full Idea: Smith argues that the theories of time which appear in the Special and General Theories of Relativity and in orthodox quantum mechanics are false metaphysical theories, based on verificationist assumptions. | |
| From: report of Quentin Smith (Absolute Simultaneity and Infinity of Time [1998]) by Robin Le Poidevin - Intro to 'Questions of Time and Tense' 4 | |
| A reaction: I wouldn't have to confidence to stand up to the panoply of modern scientists, but I am glad Quentin Smith is having a go. I love Shoemaker's three worlds example, which defies all physics. |