5 ideas
| 13832 | Natural deduction shows the heart of reasoning (and sequent calculus is just a tool) [Gentzen, by Hacking] |
| Full Idea: Gentzen thought that his natural deduction gets at the heart of logical reasoning, and used the sequent calculus only as a convenient tool for proving his chief results. | |
| From: report of Gerhard Gentzen (Investigations into Logical Deduction [1935]) by Ian Hacking - What is Logic? §05 |
| 22485 | Non-cognitivists give the conditions of use of moral sentences as facts about the speaker [Foot] |
| Full Idea: What all these [non-cognitivist] theories try to do is to give the conditions of use of sentences such as 'It is morally objectionable to break promises', in terms of something which must be true about the speaker. | |
| From: Philippa Foot (Does Moral Subjectivism Rest on a Mistake? [1995], p.192) | |
| A reaction: A wonderfully simple and accurate analysis of this view. Compare analysing 'there is a bus coming towards you' in the same way. Sounds silly, but lots of modern philosophers see things that way. |
| 22486 | The mistake is to think good grounds aren't enough for moral judgement, which also needs feelings [Foot] |
| Full Idea: The mistake is to think that whatever 'grounds' for a moral judgement may have been given, someone may be unready, indeed unable, to make the moral judgement, because he has not got the attitude or feeling. | |
| From: Philippa Foot (Does Moral Subjectivism Rest on a Mistake? [1995], p.192) | |
| A reaction: This is roughly the Frege-Geach problem for expressivism, of how we still make moral judgements about situations where we ourselves are entirely disinterested (such as ancient historical events). |
| 22487 | Moral arguments are grounded in human facts [Foot] |
| Full Idea: The grounding of a moral argument is ultimately in facts about human life. | |
| From: Philippa Foot (Does Moral Subjectivism Rest on a Mistake? [1995], p.207) | |
| A reaction: The best slogan I can find for summarising Foot's metaethics. The facts she refers to the basic human needs. She is right, and this almost bridges the fact-value divide (as long as you give a damn about human needs). |
| 9425 | Lewis later proposed the axioms at the intersection of the best theories (which may be few) [Mumford on Lewis] |
| Full Idea: Later Lewis said we must choose between the intersection of the axioms of the tied best systems. He chose for laws the axioms that are in all the tied systems (but then there may be few or no axioms in the intersection). | |
| From: comment on David Lewis (Subjectivist's Guide to Objective Chance [1980], p.124) by Stephen Mumford - Laws in Nature |