[[Poset]] # Preorder A **preoder** is a [[Poset]] without the property of antisymmetry, #m/def/order i.e. a set equipped with a relation $R$ such that $R$ (viewed here as a set) is 1. **reflexive** — for all $a \in S$, $(a,a) \in R$ 2. **transitive** — if $(a,b) \in R$ and $(b,c) \in R$, then $(a, c) \in R$ A preorder is equivalent to a [[Thin category]], see [[Preorders as categories]]. # --- #state/tidy | #lang/en | #SemBr