8 ideas
| 13768 | Validity can preserve certainty in mathematics, but conditionals about contingents are another matter [Edgington] |
| Full Idea: If your interest in logic is confined to applications to mathematics or other a priori matters, it is fine for validity to preserve certainty, ..but if you use conditionals when arguing about contingent matters, then great caution will be required. | |
| From: Dorothy Edgington (Conditionals [2001], 17.2.1) |
| 13770 | There are many different conditional mental states, and different conditional speech acts [Edgington] |
| Full Idea: As well as conditional beliefs, there are conditional desires, hopes, fears etc. As well as conditional statements, there are conditional commands, questions, offers, promises, bets etc. | |
| From: Dorothy Edgington (Conditionals [2001], 17.3.4) |
| 13764 | Are conditionals truth-functional - do the truth values of A and B determine the truth value of 'If A, B'? [Edgington] |
| Full Idea: Are conditionals truth-functional - do the truth values of A and B determine the truth value of 'If A, B'? Are they non-truth-functional, like 'because' or 'before'? Do the values of A and B, in some cases, leave open the value of 'If A,B'? | |
| From: Dorothy Edgington (Conditionals [2001], 17.1) | |
| A reaction: I would say they are not truth-functional, because the 'if' asserts some further dependency relation that goes beyond the truth or falsity of A and B. Logical ifs, causal ifs, psychological ifs... The material conditional ⊃ is truth-functional. |
| 13765 | 'If A,B' must entail ¬(A & ¬B); otherwise we could have A true, B false, and If A,B true, invalidating modus ponens [Edgington] |
| Full Idea: If it were possible to have A true, B false, and If A,B true, it would be unsafe to infer B from A and If A,B: modus ponens would thus be invalid. Hence 'If A,B' must entail ¬(A & ¬B). | |
| From: Dorothy Edgington (Conditionals [2001], 17.1) | |
| A reaction: This is a firm defence of part of the truth-functional view of conditionals, and seems unassailable. The other parts of the truth table are open to question, though, if A is false, or they are both true. |
| 22258 | Passion for progress is always short-lived [Sandel] |
| Full Idea: Progress demands passions that cannot last for long. | |
| From: Michael J. Sandel (Beyond Individualism [1988], p.35) | |
| A reaction: The obvious example, for me, is the Labour Government in the UK, 1945-51. This is the kind of realism which progressive politicians must face up to. Unfortunately it is the logic of very ruthless revolutionaries. |
| 22259 | Conservatives are either individualistic, or communal [Sandel] |
| Full Idea: Individualist conservatives believe people should be free to do as they please so long as they do not harm others. ...Communal conservatives, by contrast, believe government should affirm moral and religious values. | |
| From: Michael J. Sandel (Beyond Individualism [1988], p.38) | |
| A reaction: Nozick represents the first group (as does J.S.Mill, usually seen as epitomising liberalism). He says the first group like volunteer armies and oppose welfare; the second group favour conscription and conservative welfare. |
| 22260 | Modern liberalism fails to articulate a vision of the common good [Sandel] |
| Full Idea: In recent years liberalism has faltered because of its failure to argue for a vision of the common good. | |
| From: Michael J. Sandel (Beyond Individualism [1988], p.45) | |
| A reaction: This is Sandel's main theme. He derives his concept of the common good from the essential natures of persons and institutions. I greatly admire this. |
| 19673 | Galileo mathematised movement, and revealed its invariable component - acceleration [Galileo, by Meillassoux] |
| Full Idea: Galileo conceives of movement in mathematical terms. ...In doing so, he uncovered, beyond the variations of position and speed, the mathematical invariant of movement - that is to say, acceleration. | |
| From: report of Galileo Galilei (Two Chief World Systems [1632]) by Quentin Meillassoux - After Finitude; the necessity of contingency 5 | |
| A reaction: That is a very nice advert for the mathematical physics which replaced the Aristotelian substantial forms. ...And yet, is acceleration some deep fact about nature, or a concept which is only needed if you insist on being mathematical? |