9 ideas
| 10053 | Geometrical axioms imply the propositions, but the former may not be true [Russell] |
| Full Idea: We must only assert of various geometries that the axioms imply the propositions, not that the axioms are true and therefore that the propositions are true. | |
| From: Bertrand Russell (Foundations of Geometry [1897], Intro vii), quoted by Alan Musgrave - Logicism Revisited §4 | |
| A reaction: Clearly the truth of the axioms can remain a separate issue from whether they actually imply the theorems. The truth of the axioms might be as much a metaphysical as an empirical question. Musgrave sees this as the birth of if-thenism. |
| 10052 | Geometry is united by the intuitive axioms of projective geometry [Russell, by Musgrave] |
| Full Idea: Russell sought what was common to Euclidean and non-Euclidean systems, found it in the axioms of projective geometry, and took a Kantian view of them. | |
| From: report of Bertrand Russell (Foundations of Geometry [1897]) by Alan Musgrave - Logicism Revisited §4 | |
| A reaction: Russell's work just preceded Hilbert's famous book. Tarski later produced some logical axioms for geometry. |
| 21315 | A tree remains the same in the popular sense, but not in the strict philosophical sense [Butler] |
| Full Idea: When a man swears to the same tree having stood for fifty years in the same place, he means ...not that the tree has been all that time the same in the strict philosophical sense of the word. ...In a loose and popular sense they are said to be the same. | |
| From: Joseph Butler (Analogy of Religion [1736], App.1) | |
| A reaction: A helpful distinction which we should hang on. Of course, by the standards of modern physics, nothing is strictly the same from one Planck time to the next. All is flux. So we either drop the word 'same' (for objects) or relax a bit. |
| 21317 | Despite consciousness fluctuating, we are aware that it belongs to one person [Butler] |
| Full Idea: Though the successive consciousnesses which we have of our own existence are not the same, yet they are consciousnesses of one and the same thing or object; of the same person, self, or living agent. | |
| From: Joseph Butler (Analogy of Religion [1736], App.1) | |
| A reaction: Butler's arguments seems to be that he appears to be the same person, so he is the same person. He is explicitly disagreeing with Locke. |
| 21313 | If consciousness of events makes our identity, then if we have forgotten them we didn't exist then [Butler] |
| Full Idea: Though consciousness of what is past does ascertain our personal identity to ourselves, yet to say that it makes personal identity, or is necessary to our being the same persons is to say a person has not existed a single moment but what he can remember. | |
| From: Joseph Butler (Analogy of Religion [1736], App.1) | |
| A reaction: An over-cautious scepticism has crept in about the reliability of bodily identity. Now we can have photographs and CCTV to prove that we experienced events we have forgotten. Butler is right. |
| 21314 | Consciousness presupposes personal identity, so it cannot constitute it [Butler] |
| Full Idea: One would think it really self-evident that consciousness of personal identity presupposes, and therefore cannot constitute, personal identity, any more than knowledge can presuppose truth, which it presupposes. | |
| From: Joseph Butler (Analogy of Religion [1736], App.1) | |
| A reaction: It rather begs the question to dogmatically assert that mere consciousness presupposes a self, especially after Hume's criticisms. That consciousness implies a subject to experience needs arguing for. Is it the best explanation? |
| 21318 | If the self changes, we have no responsibilities, and no interest in past or future [Butler] |
| Full Idea: If personality is a transient thing ...then it follows that it is a fallacy to charge ourselves with any thing we did, or to imagine our present selves interested in any thing which befell us yesterday, or what will befall us tomorrow. | |
| From: Joseph Butler (Analogy of Religion [1736], App.1) | |
| A reaction: We seem to care about the past and future of our children, without actually being our children. Can't my future self be my descendant, a close one, instead of me? |
| 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 |
| 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. |