14 ideas
| 11970 | Logicians like their entities to exhibit a maximum degree of purity [Kaplan] |
| Full Idea: Logicians like their entities to exhibit a maximum degree of purity. | |
| From: David Kaplan (Transworld Heir Lines [1967], p.97) | |
| A reaction: An important observation, which explains why the modern obsession with logic has often led us down the metaphysical primrose path to ontological hell. |
| 15148 | Powers give explanations, without being necessary for some class membership [Chakravartty] |
| Full Idea: Powers explain behaviours regardless of whether they are necessary for membership in a particular class of things. | |
| From: Anjan Chakravarrty (Inessential Aristotle: Powers without Essences [2012], 3) | |
| A reaction: This seems right, and is important for driving a wedge between powers and essences. If there are essences, they are not simply some bunch of powers. |
| 11969 | Models nicely separate particulars from their clothing, and logicians often accept that metaphysically [Kaplan] |
| Full Idea: The use of models is so natural to logicians ...that they sometimes take seriously what are only artefacts of the model, and adopt a bare particular metaphysics. Why? Because the model so nicely separates the bare particular from its clothing. | |
| From: David Kaplan (Transworld Heir Lines [1967], p.97) | |
| A reaction: See also Idea 11970. I think this observation is correct, and incredibly important. We need to keep quite separate the notion of identity in conceptual space from our notion of identity in the actual world. The first is bare, the second fat. |
| 15145 | A kind essence is the necessary and sufficient properties for membership of a class [Chakravartty] |
| Full Idea: The modern concept of a kind essence is a set of intrinsic properties that are individually necessary and jointly sufficient for the membership of something in a class of things, or 'kind'. | |
| From: Anjan Chakravarrty (Inessential Aristotle: Powers without Essences [2012], 2) | |
| A reaction: I am always struck by the problem that the kind itself is constructed from the individuals, so circularity always seems to loom. |
| 15147 | Cluster kinds are explained simply by sharing some properties, not by an 'essence' [Chakravartty] |
| Full Idea: The fact that members of some cluster kinds are subjects of causal generalizations reflects the degree to which they share causally efficacious properties, not the fact that they may be composed of essence kinds per se. | |
| From: Anjan Chakravarrty (Inessential Aristotle: Powers without Essences [2012], 2) | |
| A reaction: I think this is right. I am a fan of individual essences, but not of kind essences. I take kinds, and kind explanations, to be straightforward inductive generalisations from individuals. Extreme stabilities give the illusion of a kind essence. |
| 11971 | The simplest solution to transworld identification is to adopt bare particulars [Kaplan] |
| Full Idea: If we adopt the bare particular metaphysical view, we have a simple solution to the transworld identification problem: we identify by bare particulars. | |
| From: David Kaplan (Transworld Heir Lines [1967], p.98) | |
| A reaction: See Ideas 11969 and 11970 on this idea. The problem with bare particulars is that they can change their properties utterly, so that Aristotle in the actual world can be a poached egg in some possible world. We need essences. |
| 11973 | Unusual people may have no counterparts, or several [Kaplan] |
| Full Idea: An extremely vivid person might have no counterparts, and Da Vinci seems to me to have more than one essence. Bertrand Russell is clearly the counterpart of at least three distinct persons in some more plausible world. | |
| From: David Kaplan (Transworld Heir Lines [1967], p.100) | |
| A reaction: Lewis prefers the notion that there is at most one counterpart, the 'closest' entity is some world. I think he also claims there is at least one counterpart. I like Kaplan's relaxed attitude to these things, which has more explanatory power. |
| 11972 | Essence is a transworld heir line, rather than a collection of properties [Kaplan] |
| Full Idea: I prefer to think of essence as a transworld heir line, rather than as the more familiar collection of properties, because the latter too much suggests the idea of a fixed and final essential description. | |
| From: David Kaplan (Transworld Heir Lines [1967], p.100) | |
| A reaction: He is sympathetic to the counterpart idea, and close to Lewis's view of essences, as the intersection of counterparts. I like his rebellion against fixed and final descriptions, but am a bit doubtful about his basic idea. Causation should be involved. |
| 15144 | Explanation of causal phenomena concerns essential kinds - but also lack of them [Chakravartty] |
| Full Idea: Scientific practices such as prediction and explanation regarding causal phenomena are concerned not merely with kinds having essences, but also with kinds lacking them. | |
| From: Anjan Chakravarrty (Inessential Aristotle: Powers without Essences [2012], 1) | |
| A reaction: Not quite clear what he has in mind, but explanation should certainly involve a coherent picture, and not just the citation of some underlying causal mechanism. |
| 11967 | Sentences might have the same sense when logically equivalent - or never have the same sense [Kaplan] |
| Full Idea: Among the proposals for conditions under which two sentences have the same ordinary sense, the most liberal (Carnap and Church) is that they be logically equivalent, and the most restrictive (Benson Mates) is that they never have the same sense. | |
| From: David Kaplan (Transworld Heir Lines [1967], p.89) | |
| A reaction: Personally I would move the discussion to the level of the propositions being expressed before I attempted a solution. |
| 1748 | Archelaus was the first person to say that the universe is boundless [Archelaus, by Diog. Laertius] |
| Full Idea: Archelaus was the first person to say that the universe is boundless. | |
| From: report of Archelaus (fragments/reports [c.450 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 02.Ar.3 |
| 15146 | Some kinds, such as electrons, have essences, but 'cluster kinds' do not [Chakravartty] |
| Full Idea: Many of the kinds we theorize about and experiment on today simply do not have essences. We can distinguish 'essence kinds', such as electrons, and 'cluster kinds', such as biological species. | |
| From: Anjan Chakravarrty (Inessential Aristotle: Powers without Essences [2012], 2) | |
| A reaction: This is an important point for essentialists. He offers a strict criterion, in Idea 15145, for mind membership, but we might allow species to have essences by just relaxing the criteria a bit, and acknowledging some vagueness, especially over time. |
| 15151 | Many causal laws do not refer to kinds, but only to properties [Chakravartty] |
| Full Idea: Causal laws often do not make reference to kinds of objects at all, but rather summarize relations between quantitative, causally efficacious properties of objects. | |
| From: Anjan Chakravarrty (Inessential Aristotle: Powers without Essences [2012], 3) | |
| A reaction: This would only be a serious challenge if it was not possible to translate talk of properties into talk of kinds, and vice versa. |
| 5989 | Archelaus said life began in a primeval slime [Archelaus, by Schofield] |
| Full Idea: Archelaus wrote that life on Earth began in a primeval slime. | |
| From: report of Archelaus (fragments/reports [c.450 BCE]) by Malcolm Schofield - Archelaus | |
| A reaction: This sounds like a fairly clearcut assertion of the production of life by evolution. Darwin's contribution was to propose the mechanism for achieving it. We should honour the name of Archelaus for this idea. |