Definition:Ordering Induced by Positivity Property

Definition
Let $\left({R, +, \circ, \le}\right)$ be an ordered ring whose zero is $0_R$ and whose unity is $1_R$.

Let $P \subseteq R$ such that:
 * $(1): \quad P + P \subseteq P$


 * $(2): \quad P \cap \left({- P}\right) = \left\{{0_R}\right\}$


 * $(3): \quad P \circ P \subseteq P$

Then the ordering $\le$ compatible with the ring structure of $R$ is called the ordering defined by (the positivity property) $P$.

Also see
This ordering is shown to exist by Positive Elements of Ordered Ring.