Combining Texts

All the ideas for 'Good and Evil', 'Symbolic Reasoning' and 'Ways Worlds Could Be'

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3 ideas

4. Formal Logic / F. Set Theory ST / 3. Types of Set / b. Empty (Null) Set
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.
10. Modality / E. Possible worlds / 2. Nature of Possible Worlds / a. Nature of possible worlds
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?
22. Metaethics / C. The Good / 1. Goodness / a. Form of the Good
'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.