7 ideas
| 13007 | Archimedes defined a straight line as the shortest distance between two points [Archimedes, by Leibniz] |
| Full Idea: Archimedes gave a sort of definition of 'straight line' when he said it is the shortest line between two points. | |
| From: report of Archimedes (fragments/reports [c.240 BCE]) by Gottfried Leibniz - New Essays on Human Understanding 4.13 | |
| A reaction: Commentators observe that this reduces the purity of the original Euclidean axioms, because it involves distance and measurement, which are absent from the purest geometry. |
| 16664 | Everything that exists is either a substance or an accident [Albert of Saxony] |
| Full Idea: Everything that exists is either a substance or an accident. | |
| From: Albert of Saxony (On 'Physics' [1357], I.18), quoted by Robert Pasnau - Metaphysical Themes 1274-1671 13.2 | |
| A reaction: This seems to be the view of those who base their ontology on first-order classical logic. The more austere reading of that makes the accidents into sets of substances, so it's just substances. All the non-substance stuff cries out for recognition. |
| 16703 | God could make a successive thing so that previous parts cease to exist [Albert of Saxony] |
| Full Idea: Something can be conceived of as successive simpliciter, with respect to both its substance and its state. For example, if Socrates were continually made and made again by the First Cause, as the Seine flow, so nothing of what preexists remains. | |
| From: Albert of Saxony (On 'Physics' [1357], III.3), quoted by Robert Pasnau - Metaphysical Themes 1274-1671 18.4 | |
| A reaction: This is precisely the problem that modern stage theory faces, of knowing how to connect the stages together. |
| 16699 | Successive entities just need parts to succeed one another, without their existence [Albert of Saxony] |
| Full Idea: For existence to hold of completely successive entities it is not required that their parts exist, but that one part succeed another, as a future part succeeds a past part. | |
| From: Albert of Saxony (On 'Physics' [1357], III.3 ad 2), quoted by Robert Pasnau - Metaphysical Themes 1274-1671 18.3 | |
| A reaction: A nice move, but it doesn't quite solve it. How can non-existent things 'succeed one another'? It is worrying for metaphysics that some things have entirely different concepts of persistence from other things. |
| 8406 | Not all explanations are causal, but if a thing can be explained at all, it can be explained causally [Sanford] |
| Full Idea: Although not all explanations are causal, anything which can be explained in any way can be explained causally. | |
| From: David H. Sanford (Causation [1995], p.79) | |
| A reaction: A nice bold claim with which I am in sympathy, but he would have a struggle proving it. Does this imply that causal explanations are basic, or in some way superior? Note that functional explanations would thus have underlying causal explanations. |
| 16570 | Elements are found last in dismantling bodies, and first in generating them [Albert of Saxony] |
| Full Idea: On one possible description, an element is what is found last when bodies are taken apart, and what is found first when bodies are generated. | |
| From: Albert of Saxony (On 'Generation and Corruption' [1356], II.3), quoted by Robert Pasnau - Metaphysical Themes 1274-1671 2.1 |
| 8407 | A totality of conditions necessary for an occurrence is usually held to be jointly sufficient for it [Sanford] |
| Full Idea: A totality of conditions necessary for an occurrence is jointly sufficient for it. This is a widely held but controversial view, and it is not a logical truth. | |
| From: David H. Sanford (Causation [1995], p.82) | |
| A reaction: This wouldn't work for an impossible occurrence. What are the necessary conditions to produce a large planet made of uranium? One of them would have to be a naturally impossible necessity. |