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Viewing Version 12 of 'well-ordering principle for natural numbers'
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Title of object: well-ordering principle for natural numbers
Canonical Name: WellOrderingPrinciple
Type: Axiom

Created on: 2001-10-16 08:37:55
Modified on: 2007-06-21 21:11:30

Creator: smw
Modifier: smw
Author: smw
Author: KimJ

Classification: msc:06F25

Preamble:

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\usepackage{graphicx}
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Content:

\PMlinkescapeword{equivalent}
Every nonempty set $S$ of natural numbers contains a least element; that is, there is some number $a$ in $S$ such that $a \leq b$ for all $b$ belonging to $S$.\\

Beware that there is another statement (which is equivalent to the axiom of choice) called the ``well-ordering principle." It asserts that every set can be well-ordered.

Note that the well-ordering principle for natural numbers is equivalent to the principle of mathematical induction (or, the principle of finite induction).