8 ideas
| 17743 | De Morgan introduced a 'universe of discourse', to replace Boole's universe of 'all things' [De Morgan, by Walicki] |
| Full Idea: In 1846 De Morgan introduced the enormously influential notion of a possibly arbitrary and stipulated 'universe of discourse'. It replaced Boole's original - and metaphysically a bit suspect - universe of 'all things'. | |
| From: report of Augustus De Morgan (works [1846]) by Michal Walicki - Introduction to Mathematical Logic History D.1.1 | |
| A reaction: This not only brings formal logic under control, but also reflects normal talk, because there is always an explicit or implicit domain of discourse when we talk. Of virtually any conversation, you can say what it is 'about'. |
| 13163 | Circles must be bounded, so cannot be infinite [Leibniz] |
| Full Idea: An infinite circle is impossible, since any circle is bounded by its circumference. | |
| From: Gottfried Leibniz (Dialogue on human freedom and origin of evil [1695], p.114) | |
| A reaction: This is interesting if one is asking what the essence of a circle must be. If is tempting to say merely that the radii must be equal, but can they have the length of some vast transfinite number? The circumference must be 2π bigger. |
| 13162 | Sloth's Syllogism: either it can't happen, or it is inevitable without my effort [Leibniz] |
| Full Idea: The ancient Sloth's Syllogism says that if something is foreseen and infallible, it will happen without my effort, and if it is not foreseen, it will not happen, even though I am able to do it. | |
| From: Gottfried Leibniz (Dialogue on human freedom and origin of evil [1695], p.113) | |
| A reaction: Presumable the foreseeing is to be done by the oracle, and not by the slothful person. |
| 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. |
| 19339 | Evil is a negation of good, which arises from non-being [Leibniz] |
| Full Idea: The cause of good is positive, but evil is a defect, that is, a privation or negation, and consequently, it arises from nothingness or nonbeing. | |
| From: Gottfried Leibniz (Dialogue on human freedom and origin of evil [1695], p.114) | |
| A reaction: He goes on to illustrate his idea from mathematics. He is modifying Augustine's view that evil is an absence of good, by adding nonbeing as the driving force behind it. Doesn't sound very persuasive to me. |
| 13164 | God only made sin possible because a much greater good can be derived from it [Leibniz] |
| Full Idea: We must believe that God would not have allowed sin nor would he have created things he knows will sin, if he could not derive from them a good incomparably greater than the resulting evil. | |
| From: Gottfried Leibniz (Dialogue on human freedom and origin of evil [1695], p.115) | |
| A reaction: Why 'must' we believe this? Do we have to imagine all the genocides shrinking to insignificance once we grasp the wonderful goods that can be derived from them? The end justifies the means. Genocide is actually a good thing. Hm. |