10 ideas
| 17833 | The first-order ZF axiomatisation is highly non-categorical [Hallett,M] |
| Full Idea: The first-order Sermelo-Fraenkel axiomatisation is highly non-categorical. | |
| From: Michael Hallett (Introduction to Zermelo's 1930 paper [1996], p.1213) |
| 17834 | Non-categoricity reveals a sort of incompleteness, with sets existing that the axioms don't reveal [Hallett,M] |
| Full Idea: The non-categoricity of the axioms which Zermelo demonstrates reveals an incompleteness of a sort, ....for this seems to show that there will always be a set (indeed, an unending sequence) that the basic axioms are incapable of revealing to be sets. | |
| From: Michael Hallett (Introduction to Zermelo's 1930 paper [1996], p.1215) | |
| A reaction: Hallett says the incompleteness concerning Zermelo was the (transfinitely) indefinite iterability of the power set operation (which is what drives the 'iterative conception' of sets). |
| 17837 | Zermelo allows ur-elements, to enable the widespread application of set-theory [Hallett,M] |
| Full Idea: Unlike earlier writers (such as Fraenkel), Zermelo clearly allows that there might be ur-elements (that is, objects other than the empty set, which have no members). Indeed he sees in this the possibility of widespread application of set-theory. | |
| From: Michael Hallett (Introduction to Zermelo's 1930 paper [1996], p.1217) |
| 17836 | The General Continuum Hypothesis and its negation are both consistent with ZF [Hallett,M] |
| Full Idea: In 1938, Gödel showed that ZF plus the General Continuum Hypothesis is consistent if ZF is. Cohen showed that ZF and not-GCH is also consistent if ZF is, which finally shows that neither GCH nor ¬GCH can be proved from ZF itself. | |
| From: Michael Hallett (Introduction to Zermelo's 1930 paper [1996], p.1217) |
| 22331 | Moral statements are imperatives rather than the avowals of emotion - but universalisable [Hare, by Glock] |
| Full Idea: According to Hare's universal prescriptivism, moral statements are closer to imperatives than to avowals of emotion; their purpose is to guide action. But unlike imeperatives they are universalisable. | |
| From: report of Richard M. Hare (Freedom and Reason [1963]) by Hans-Johann Glock - What is Analytic Philosophy? 2.9 | |
| A reaction: Why isn't 'everyone ought to support West Ham' a moral judgement? |
| 22484 | Universalised prescriptivism could be seen as implying utilitarianism [Hare, by Foot] |
| Full Idea: Hare has suggested that a fairly tight form of utilitarianism can be obtained from universalised prescriptivism. | |
| From: report of Richard M. Hare (Freedom and Reason [1963]) by Philippa Foot - Does Moral Subjectivism Rest on a Mistake? p.191 | |
| A reaction: All the benefits of Bentham, Kant and Hume, in one neat package! Since I take all three of them to be wrong about ethics, that counts against this idea. |
| 21093 | Friendship without community spirit misses out on the main part of virtue [Hume] |
| Full Idea: A man who is only susceptible of friendship, without public spirit or a regard to the community, is deficient in the most material part of virtue. | |
| From: David Hume (That Politics may be reduced to a Science [1750], p.21) | |
| A reaction: I think this is aimed at the epicureans. If the highest virtues are focused on one's friends that can easily lead to injustice, because it can tolerate prejudice against people who are very unlike one's friends. |
| 6449 | The categorical imperative leads to utilitarianism [Hare, by Nagel] |
| Full Idea: Hare has proposed that utilitarianism is the ultimate standard to which we are led by the categorical imperative. | |
| From: report of Richard M. Hare (Freedom and Reason [1963], p.123-4) by Thomas Nagel - Equality and Partiality | |
| A reaction: It seems to me better to say that Kant starts (unwittingly) from something like utilitarianism, that is, an assumption that human happiness and welfare have some sort of intrinsic value that cannot be demonstrated. Otherwise evil can be universalised. |
| 21091 | It would be absurd if even a free constitution did not impose restraints, for the public good [Hume] |
| Full Idea: A republican and free form of government would be an obvious absurdity, if the particular checks and controls, provided by the constitution, had really no influence, and made it not the interest, even of bad men, to act for the public good. | |
| From: David Hume (That Politics may be reduced to a Science [1750], p.14) | |
| A reaction: Presumably if you attain absolute power you can write any old constitution you like (Clause 1: the presidency is for life). But there does seem much point in doing it - unless it is to facilitate the use of the law for persecutions. |
| 21092 | Nobility either share in the power of the whole, or they compose the power of the whole [Hume] |
| Full Idea: A nobility may possess power in two different ways. Either every nobleman shares the power as part of the whole body, or the whole body enjoys the power as composed of parts, which each have a distinct power and authority. | |
| From: David Hume (That Politics may be reduced to a Science [1750], p.15) | |
| A reaction: He says the first type is found in Venice, and is preferable to the second type, which is found in Poland. Presumably in the shared version there is some restraint on depraved nobles. The danger is each noble being an autocrat. |