(0,1)-category

(0,1)-topos

# Contents

## Definitions

###### Definition

For $(S, \leq)$ a preorder and $A \hookrightarrow S$ a subset, an upper bound of $A$ in $S$ is an element $x$ of $S$ such that $y \leq x$ whenever $y \in A$.

Dually (in the opposite poset):

###### Definition

For $(S, \leq)$ a preorder and $A \hookrightarrow S$ a subset, a lower bound of $A$ in $S$ is an element $x$ of $S$ such that $x \leq y$ whenever $y \in A$.

Revised on September 27, 2012 23:09:15 by Toby Bartels (98.16.171.221)