Definition:Total Ordering/Definition 2

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Definition

Let $\RR \subseteq S \times S$ be a relation on a set $S$.

$\RR$ is a total ordering on $S$ if and only if:

\(\text {(1)}: \quad\) \(\ds \RR \circ \RR\) \(\subseteq\) \(\ds \RR\)
\(\text {(2)}: \quad\) \(\ds \RR \cap \RR^{-1}\) \(\subseteq\) \(\ds \Delta_S\)
\(\text {(3)}: \quad\) \(\ds \RR \cup \RR^{-1}\) \(=\) \(\ds S \times S\)


Also known as

Some sources refer to a total ordering as a linear ordering, or a simple ordering.


If it is necessary to emphasise that a total ordering $\preceq$ is not strict, then the term weak total ordering may be used.


Also see

  • Results about total orderings can be found here.


Sources