6 ideas
| 14713 | Truth in a scenario is the negation in that scenario being a priori incoherent [Chalmers] |
| Full Idea: The epistemic 1-intension for a sentence S is True at a scenario W iff (W and not-S) is a priori incoherent. | |
| From: David J.Chalmers (Epistemic Two-Dimensional Semantics [2004], p.180-4), quoted by Laura Schroeter - Two-Dimensional Semantics | |
| A reaction: See Two-Dimensional Semantics (in 'Language') and Chalmers for the background to this idea. I love the coherence view of justification, but get a bit nervous when people start defining truth in that way. |
| 14712 | A sentence is a priori if no possible way the world might actually be could make it false [Chalmers] |
| Full Idea: The Core Thesis for rationalist 2D semantics is that for any sentence S, S is apriori iff S has a necessary 1-intension. (That is, there is no possible way the world might be that, if it actually obtained, would make S false). | |
| From: David J.Chalmers (Epistemic Two-Dimensional Semantics [2004], p.165), quoted by Laura Schroeter - Two-Dimensional Semantics 2.3.2 | |
| A reaction: [The parenthesis is by Schroeter] A '1-intension' is defined by a diagonal on a 2D semantic matrix. Chalmers defends conceivability as the guide to possibility. This is a very traditional view of the a priori, expressed in modern terms. |
| 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 |
| 20646 | Helmholtz used 'energy' to mathematically link heat, light, electricity and magnetism [Helmholtz, by Watson] |
| Full Idea: Helmholtz provided the requisite mathematical formulation linking heat, light, electricity and magnetism, by treating these phenomena as different manifestations of 'energy'. | |
| From: report of Hermann von Helmholtz (On the Conservation of Force [1847]) by Peter Watson - Convergence 01 'Human' | |
| A reaction: I'm increasingly struck by the neglect by philosophers of nature of these amazing developments in 19th century physics, because they prefer the excitement of the latest nuclear physics. There is more philosophical interest in the earlier stages. |
| 20973 | All forces conserve the sum of kinetic and potential energy [Helmholtz, by Papineau] |
| Full Idea: Helmholtz crucially asserted that all forces conserve the sum of kinetic and potential energy; superficially non-conservative forces like friction are simply macroscopic manifestations of more fundamental forces conserving energy at the micro-level. | |
| From: report of Hermann von Helmholtz (On the Conservation of Force [1847]) by David Papineau - Thinking about Consciousness App 4.3 | |
| A reaction: Friction had been a problem case, because it appeared not to conserve energy when it slowed movement down. |
| 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. |