5 ideas
| 18189 | ZFC could contain a contradiction, and it can never prove its own consistency [MacLane] |
| Full Idea: We have at hand no proof that the axioms of ZFC for set theory will never yield a contradiction, while Gödel's second theorem tells us that such a consistency proof cannot be conducted within ZFC. | |
| From: Saunders MacLane (Mathematics: Form and Function [1986], p.406), quoted by Penelope Maddy - Naturalism in Mathematics | |
| A reaction: Maddy quotes this, while defending set theory as the foundation of mathematics, but it clearly isn't the most secure foundation that could be devised. She says the benefits of set theory do not need guaranteed consistency (p.30). |
| 15571 | The idea of an atemporal realm of validity is as implausible as medieval theology [Heidegger] |
| Full Idea: The whole idea of an atemporal realm of validity is an invention that is no less doubtful than medieval speculation about angels. | |
| From: Martin Heidegger (Basic Problems of Phenomenology [1927], p.215), quoted by Richard Polt - Heidegger: an introduction 2 'Theory' | |
| A reaction: This seems to be flatly opposed to the view of Frege, and shows why continental philosophy has largely eschewed a study of logic. It is hard for a philosopher to pursue logic extensively without commitment to the Fregean Third Realm. |
| 15581 | Dasein is always only that which it has chosen to be [Heidegger] |
| Full Idea: Dasein is always only that which it has chosen to be. | |
| From: Martin Heidegger (Basic Problems of Phenomenology [1927], p.278), quoted by Richard Polt - Heidegger: an introduction 3.§39-42 | |
| A reaction: I take it as significant that this is what it 'has' chosen, and not what it now 'chooses'. I might accept that my mode of existence results from past choices, but certainly not that I can choose it now. Ossified brain. |
| 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. |