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Single Idea 17801

[filed under theme 4. Formal Logic / F. Set Theory ST / 5. Conceptions of Set / e. Iterative sets ]

Full Idea

The idea of 'generating' sets is only a metaphor - the existence of the hierarchy is established without appealing to such dubious notions.

Gist of Idea

The set hierarchy doesn't rely on the dubious notion of 'generating' them

Source

John Mayberry (What Required for Foundation for Maths? [1994], p.414-2)

Book Ref

'Philosophy of Mathematics: anthology', ed/tr. Jacquette,Dale [Blackwell 2002], p.414


A Reaction

Presumably there can be a 'dependence' or 'determination' relation which does not involve actual generation.


The 15 ideas with the same theme [sets as a well-founded hierarchy built from scratch]:

The iterative conception says sets are formed at stages; some are 'earlier', and must be formed first [Boolos]
The iterative conception may not be necessary, and may have fixed points or infinitely descending chains [Hart,WD]
The set hierarchy doesn't rely on the dubious notion of 'generating' them [Mayberry]
There is no stage at which we can take all the sets to have been generated [Fine,K]
The Iterative Conception says everything appears at a stage, derived from the preceding appearances [Maddy]
Russell's paradox shows that there are classes which are not iterative sets [Shapiro]
It is central to the iterative conception that membership is well-founded, with no infinite descending chains [Shapiro]
Iterative sets are not Boolean; the complement of an iterative set is not an iterative sets [Shapiro]
The 'iterative' view says sets start with the empty set and build up [Brown,JR]
In the iterative conception of sets, they form a natural hierarchy [Swoyer]
Nowadays we derive our conception of collections from the dependence between them [Potter]
The iterative conception of set wasn't suggested until 1947 [Lavine]
The iterative conception needs the Axiom of Infinity, to show how far we can iterate [Lavine]
The iterative conception doesn't unify the axioms, and has had little impact on mathematical proofs [Lavine]
The iterative conception has to appropriate Replacement, to justify the ordinals [Hossack]