Ideas from 'Symbolic Reasoning' by Hugh MacColl [1905], by Theme Structure

[found in 'Mind' (ed/tr -) [- ,]].

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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
                        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.