10 ideas
10304 | Very few things in set theory remain valid in intuitionist mathematics [Bernays] |
Full Idea: Very few things in set theory remain valid in intuitionist mathematics. | |
From: Paul Bernays (On Platonism in Mathematics [1934]) |
10801 | Either reference really matters, or we don't need to replace it with substitutions [Quine] |
Full Idea: When we reconstrue quantification in terms of substituted expressions rather than real values, we waive reference. ...but if reference matters, we cannot afford to waive it as a category; and if it does not, we do not need to. | |
From: Willard Quine (Reply to Professor Marcus [1962], p.183) | |
A reaction: An odd dilemma to pose. Presumably the substitution account is an attempt to explain how language actually works, without mentioning dubious direct ontological commitment in the quantifiers. |
10303 | Restricted Platonism is just an ideal projection of a domain of thought [Bernays] |
Full Idea: A restricted Platonism does not claim to be more than, so to speak, an ideal projection of a domain of thought. | |
From: Paul Bernays (On Platonism in Mathematics [1934], p.261) | |
A reaction: I have always found Platonism to be congenial when it talks of 'ideals', and ridiculous when it talks of a special form of 'existence'. Ideals only 'exist' because we idealise things. I may declare myself, after all, to be a Restricted Platonist. |
10306 | Mathematical abstraction just goes in a different direction from logic [Bernays] |
Full Idea: Mathematical abstraction does not have a lesser degree than logical abstraction, but rather another direction. | |
From: Paul Bernays (On Platonism in Mathematics [1934], p.268) | |
A reaction: His point is that the logicists seem to think that if you increasingly abstract from mathematics, you end up with pure logic. |
3785 | You can't separate acts from the people performing them [Glover] |
Full Idea: A mistake of consequentialists is to treat actions as though they can somehow be isolated from the people performing them. | |
From: Jonathan Glover (Introductions to Utilitarianism and its Critics [1990], Pt Five) | |
A reaction: I agree. The weather produces consequences. Morality is about people. Crocodiles, for example, are exempt. |
3786 | Aggression in defence may be beneficial but morally corrupting [Glover] |
Full Idea: Forming the intention to use nuclear retaliation if attacked may both be the best way to avoid the catastrophe of nuclear war and at the same time be morally corrupting. | |
From: Jonathan Glover (Introductions to Utilitarianism and its Critics [1990], Pt Five) | |
A reaction: A famous moment in 2017 when Jeremy Corbyn refused to say he would be willing to use the weapons, if elected. It would be hard to sustain a determination to do it, and then reject it at the crucial moment. |
3784 | Duty prohibits some acts, whatever their consequences [Glover] |
Full Idea: The deontological view is that some acts are absolutely prohibited, regardless of consequences. | |
From: Jonathan Glover (Introductions to Utilitarianism and its Critics [1990], Pt Five) |
3782 | Satisfaction of desires is not at all the same as achieving happiness [Glover, by PG] |
Full Idea: Objections to utilitarianism as maximisation of preferences: faded past desires or the desires of the dead; obtaining desires and happiness are different; fewer desires are easier to satisfy; pain is good if it can be removed. | |
From: report of Jonathan Glover (Introductions to Utilitarianism and its Critics [1990], Pt Two) by PG - Db (ideas) |
3787 | Rule-utilitarianism is either act-utilitarianism, or not really utilitarian [Glover] |
Full Idea: Rule-utilitarianism seems either to collapse into act-utilitarianism, or else it is only partly utilitarian. | |
From: Jonathan Glover (Introductions to Utilitarianism and its Critics [1990], Pt Six) |
3783 | How can utilitarianism decide the ideal population size? [Glover] |
Full Idea: There are deep problems for utilitarianism in trying to work out what the ideal population size would be. | |
From: Jonathan Glover (Introductions to Utilitarianism and its Critics [1990], Pt Four) |