7 ideas
| 21962 | Metaphysics is the roots of the tree of science [Descartes] |
| Full Idea: The whole of philosophy is like a tree. The roots are metaphysics, the trunk is physics, and the branches emerging from the trunk are all the other sciences. | |
| From: René Descartes (Preface to 'Principles of Philosophy' [1647]), quoted by A.W. Moore - The Evolution of Modern Metaphysics 01.2 | |
| A reaction: If Descartes had not believed this he would not have bothered with metaphysics, and philosophy might have been dead by 1650. |
| 3659 | I know the truth that God exists and is the author of truth [Descartes] |
| Full Idea: I have very clearly deduced the following truths, that there is a God who is the author of all that is in the world, and who is the source of all truth. | |
| From: René Descartes (Preface to 'Principles of Philosophy' [1647], p.180) |
| 9390 | Logic guides thinking, but it isn't a substitute for it [Rumfitt] |
| Full Idea: Logic is part of a normative theory of thinking, not a substitute for thinking. | |
| From: Ian Rumfitt (The Logic of Boundaryless Concepts [2007], p.13) | |
| A reaction: There is some sort of logicians' dream, going back to Leibniz, of a reasoning engine, which accepts propositions and outputs inferences. I agree with this idea. People who excel at logic are often, it seems to me, modest at philosophy. |
| 13128 | 'Ultimate sortals' cannot explain ontological categories [Westerhoff on Wiggins] |
| Full Idea: 'Ultimate sortals' are said to be non-subordinated, disjoint from one another, and uniquely paired with each object. Because of this, the ultimate sortal cannot be a satisfactory explication of the notion of an ontological category. | |
| From: comment on David Wiggins (Identity and Spatio-Temporal Continuity [1971], p.75) by Jan Westerhoff - Ontological Categories §26 | |
| A reaction: My strong intuitions are that Wiggins is plain wrong, and Westerhoff gives the most promising reasons for my intuition. The simplest point is that objects can obviously belong to more than one category. |
| 9389 | Vague membership of sets is possible if the set is defined by its concept, not its members [Rumfitt] |
| Full Idea: Vagueness in respect of membership is consistency with determinacy of the set's identity, so long as a set's identity is taken to consist, not in its having such-and-such members, but in its being the extension of a concept. | |
| From: Ian Rumfitt (The Logic of Boundaryless Concepts [2007], p.5) | |
| A reaction: I find this view of sets much more appealing than the one that identifies a set with its members. The empty set is less of a problem, as well as non-existents. Logicians prefer the extensional view because it is tidy. |
| 3657 | Understanding, not the senses, gives certainty [Descartes] |
| Full Idea: Certainty is not in the sense but in the understanding alone, when it has evident perceptions. | |
| From: René Descartes (Preface to 'Principles of Philosophy' [1647], p.177) |
| 3660 | Atheism arises from empiricism, because God is intangible [Descartes] |
| Full Idea: The existence of God has been doubted by some, because they attributed too much to the perceptions of the senses, and God can be neither seen nor touched. | |
| From: René Descartes (Preface to 'Principles of Philosophy' [1647], p.180) |