6 ideas
| 19404 | Necessities rest on contradiction, and contingencies on sufficient reason [Leibniz] |
| Full Idea: The principle of contradiction is the principle of necessity, and the principle that a sufficient reason must be given is the principle of contingency. | |
| From: Gottfried Leibniz (On Sufficient Reason [1686], p.95) | |
| A reaction: [this paragraph is actually undated] Contradictions occur in concrete actuality, as well as in theories and formal systems. If so, then there are necessities in nature. Are they discoverable a posteriori? Leibniz says not. |
| 9100 | Our intellect only assents to what we believe to be true [William of Ockham] |
| Full Idea: Our intellect does not assent to anything unless we believe it to be true. | |
| From: William of Ockham (Prologue to Ordinatio [1320], Q 1 N sqq) | |
| A reaction: This strikes me as being a much more accurate and commonsense view of belief than that of Hume, who simply views it phenomenologically. ...But then the remark appears to be circular. Belief requires a belief that it is true. Hm. |
| 9101 | Abstractive cognition knows universals abstracted from many singulars [William of Ockham] |
| Full Idea: Abstractive cognition (in one sense) relates to something abstracted from many singulars; and in this sense abstractive cognition is nothing else but cognition of a universal which can be abstracted from many things. | |
| From: William of Ockham (Prologue to Ordinatio [1320], Q 1 N sqq) | |
| A reaction: This strikes me as being correct common sense, even though it has become deeply unfashionable since Frege. We may not be able to see quite how the mind manages to see universals in a bunch of objects, but there is no better story. |
| 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 |
| 19403 | Each of the infinite possible worlds has its own laws, and the individuals contain those laws [Leibniz] |
| Full Idea: As there are an infinity of possible worlds, there are also an infinity of laws, some proper to one, another to another, and each possible individual of any world contains in its own notion the laws of its world. | |
| From: Gottfried Leibniz (On Sufficient Reason [1686], p.95) | |
| A reaction: Hence Leibniz is not really a scientific essentialist, in that he doesn't think the laws arise out of the nature of the matter consituting the world. I wonder if the primitive matter of bodies which attaches to the monads is the same in each world? |
| 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. |