Well-ordered set

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Note: This page exists only to contain a simpler, easier view of Well-ordering - until all the concepts can be united anyway.

Definition

A set A with an linear ordering <⊆A×A where if (a,b)∈< we write a<b is said to be well ordered[1] if:

  • Every nonempty subset of A has a least element

That is to say that:

  • XP(A)pXxX[p=pp<x]

Or more simply:

  • XP(A)pXxX[px][Note 1]

Notes

  1. <cite_references_link_accessibility_label> Recall that for every linear ordering > there exists a corresponding partial ordering and for every there exists a corresponding >

References

  1. <cite_references_link_accessibility_label> Topology - James R. Munkres - Second Edition