3 ideas
21548 | The null class is the class with all the non-existents as its members [MacColl, by Lackey] |
Full Idea: In 1905 the Scottish logician Hugh MacColl published a paper in which he argued that the null class in logic should be taken as the class with all the non-existents as its members. | |
From: report of Hugh MacColl (Symbolic Reasoning [1905]) by Douglas Lackey - Intros to Russell's 'Essays in Analysis' p.95 | |
A reaction: For the null object (zero) Frege just chose one sample concept with an empty extension. MacColl's set seems to have a lot of members, given that it is 'null'. How many, I wonder? Russell responded to this paper. |
15432 | Structural universals might serve as possible worlds [Forrest, by Lewis] |
Full Idea: Forrest proposed that structural universals should serve as ersatz possible worlds. | |
From: report of Peter Forrest (Ways Worlds Could Be [1986]) by David Lewis - Against Structural Universals 'Intro' | |
A reaction: I prefer powers to property universals. Perhaps a possible world is a maximal set of co-existing dispositions? |
22489 | 'Good' is an attributive adjective like 'large', not predicative like 'red' [Geach, by Foot] |
Full Idea: Geach puts 'good' in the class of attributive adjectives, such as 'large' and 'small', contrasting such adjectives with 'predicative' adjectives such as 'red'. | |
From: report of Peter Geach (Good and Evil [1956]) by Philippa Foot - Natural Goodness Intro | |
A reaction: [In Analysis 17, and 'Theories of Ethics' ed Foot] Thus any object can simply be red, but something can only be large or small 'for a rat' or 'for a car'. Hence nothing is just good, but always a good so-and-so. This is Aristotelian, and Foot loves it. |