9 ideas
| 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. |
| 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. |
| 23633 | Many truths seem obvious, and point to universal agreement - which is what we find [Reid] |
| Full Idea: There are many truths so obvious to the human faculties, that it should be expected that men should universally agree in them. And this is actually found to be the case with regard to many truths, against which we find no dissent. | |
| From: Thomas Reid (Essays on Intellectual Powers 1: Preliminary [1785], 2) | |
| A reaction: He says that a few sceptical philosophers may disagree. This is a nice statement of his creed of common sense. I agree with him, and Aristotle observes the same fact. |
| 23630 | Only philosophers treat ideas as objects [Reid] |
| Full Idea: The vulgar allow that an 'idea' implies a mind that thinks, an act of mind which we call thinking, and an object about which we think. But the philosopher conceives a fourth - the idea, which is the immediate object. …I believe this to be a mere fiction. | |
| From: Thomas Reid (Essays on Intellectual Powers 1: Preliminary [1785], 1) | |
| A reaction: Another example, to add to Yablo's list, of abstract objects invented by philosophers to fill holes in their theories. This one is illuminating, because we all say 'I've got an idea'. Cf discussions of the redundancy of truth. Cf propositions. |
| 23629 | The ambiguity of words impedes the advancement of knowledge [Reid] |
| Full Idea: There is no greater impediment to the advancement of knowledge than the ambiguity of words. | |
| From: Thomas Reid (Essays on Intellectual Powers 1: Preliminary [1785], 1) | |
| A reaction: He means that ambiguity leads to long pointless disagreements. |
| 4692 | It is not true that killing and allowing to die (or acts and omissions) are morally indistinguishable [Foot] |
| Full Idea: Many philosophers (e.g. Rachels) have argued that there is no morally relevant distinction between killing and allowing to die (or the related 'acts and omissions'),..as in not sending food, or sending poisoned food. I disagree. | |
| From: Philippa Foot (Killing and Letting Die [1985], p.78) | |
| A reaction: It appears that some omissions are worse than acts. It is more honest to just shoot an injured person, than to walk away and leave them to die. A range of cases. |
| 4694 | Making a runaway tram kill one person instead of five is diverting a fatal sequence, not initiating one [Foot] |
| Full Idea: If a runaway tram is heading towards a track on which five people are standing, and there is someone who can switch the points, diverting it onto a track where there is one person,...this is diverting a fatal sequence, not starting a new one. | |
| From: Philippa Foot (Killing and Letting Die [1985], p.85) | |
| A reaction: Suppose the one person was of immense community value, or someone you personally hated? Clearly she is interested in the agent's virtue, rather than the actual consequences. |
| 4693 | The right of non-interference (with a 'negative duty'), and the right to goods/services ('positive') [Foot] |
| Full Idea: There are rights to non-interference (and their corresponding "negative duties"), and the rights to goods and services (with corresponding "positive duties"). Interference usually needs more justification than withholding goods. | |
| From: Philippa Foot (Killing and Letting Die [1985], p.82) | |
| A reaction: This invites the question of which is the stronger, and whether paternalism can overrule non-interference, or an expectation of self-sufficiency overrule the positive rights. |
| 23632 | Similar effects come from similar causes, and causes are only what are sufficient for the effects [Reid] |
| Full Idea: A first principle is that similar effects proceed from the same or similar causes; that we ought to admit of no other causes …but such as are sufficient to account for the effects. | |
| From: Thomas Reid (Essays on Intellectual Powers 1: Preliminary [1785], 2) | |
| A reaction: He treats these as a priori axioms of natural philosophy. In evolution similar causes seem to produce startlingly divergent effects, such as the mating needs of male birds. |