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Single Idea 10878

[filed under theme 4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / f. Axiom of Infinity V ]

Full Idea

Axiom of Infinity: There exists a set containing the empty set and the successor of each of its elements.

Gist of Idea

Infinity: There exists a set of the empty set and the successor of each element

Source

Brian Clegg (Infinity: Quest to Think the Unthinkable [2003], Ch.15)

Book Ref

Clegg,Brian: 'Infinity' [Robinson 2003], p.206


A Reaction

This is rather different from the other axioms because it contains the notion of 'successor', though that can be generated by an ordering procedure.

Related Idea

Idea 15931 The iterative conception needs the Axiom of Infinity, to show how far we can iterate [Lavine]


The 20 ideas from Brian Clegg

Transcendental numbers can't be fitted to finite equations [Clegg]
Either lack of zero made early mathematics geometrical, or the geometrical approach made zero meaningless [Clegg]
By adding an axis of imaginary numbers, we get the useful 'number plane' instead of number line [Clegg]
Beyond infinity cardinals and ordinals can come apart [Clegg]
An ordinal number is defined by the set that comes before it [Clegg]
A set is 'well-ordered' if every subset has a first element [Clegg]
Set theory made a closer study of infinity possible [Clegg]
Any set can always generate a larger set - its powerset, of subsets [Clegg]
The 'continuum hypothesis' says aleph-one is the cardinality of the reals [Clegg]
Cantor's account of infinities has the shaky foundation of irrational numbers [Clegg]
The Continuum Hypothesis is independent of the axioms of set theory [Clegg]
Extensionality: Two sets are equal if and only if they have the same elements [Clegg]
Specification: a condition applied to a set will always produce a new set [Clegg]
Powers: All the subsets of a given set form their own new powerset [Clegg]
Choice: For every set a mechanism will choose one member of any non-empty subset [Clegg]
Axiom of Existence: there exists at least one set [Clegg]
Infinity: There exists a set of the empty set and the successor of each element [Clegg]
Pairing: For any two sets there exists a set to which they both belong [Clegg]
Unions: There is a set of all the elements which belong to at least one set in a collection [Clegg]
Mathematics can be 'pure' (unapplied), 'real' (physically grounded); or 'applied' (just applicable) [Clegg]