5 ideas
| 17743 | De Morgan introduced a 'universe of discourse', to replace Boole's universe of 'all things' [De Morgan, by Walicki] |
| Full Idea: In 1846 De Morgan introduced the enormously influential notion of a possibly arbitrary and stipulated 'universe of discourse'. It replaced Boole's original - and metaphysically a bit suspect - universe of 'all things'. | |
| From: report of Augustus De Morgan (works [1846]) by Michal Walicki - Introduction to Mathematical Logic History D.1.1 | |
| A reaction: This not only brings formal logic under control, but also reflects normal talk, because there is always an explicit or implicit domain of discourse when we talk. Of virtually any conversation, you can say what it is 'about'. |
| 16620 | A chair is wood, and its shape is the form; it isn't 'compounded' of the matter and form [Hobbes] |
| Full Idea: Nothing can be compounded of matter and form. The matter of a chair is wood; the form is the figure it has, apt for the intended use. Does his Lordship think the chair compounded of the wood and the figure? | |
| From: Thomas Hobbes (Letter to Bramhall [1650], 4:302), quoted by Robert Pasnau - Metaphysical Themes 1274-1671 07.1 | |
| A reaction: Aristotle does use the word 'shape' [morphe] when he is discussing hylomorphism, and the statue example seems to support it, but elsewhere the form is a much deeper principle of individuation. |
| 16622 | Essence is just an artificial word from logic, giving a way of thinking about substances [Hobbes] |
| Full Idea: Essence and all other abstract names are words artificial belonging to the art of logic, and signify only the manner how we consider the substance itself. | |
| From: Thomas Hobbes (Letter to Bramhall [1650], 4:308), quoted by Robert Pasnau - Metaphysical Themes 1274-1671 | |
| A reaction: I sympathise quite a lot with this view, but not with its dismissive tone. The key question I take to be: if you reject essences entirely (having read too much physics), how are we going to think about entities in the world in future? |
| 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. |