User:KBlott/Definition/Class

Preamble
Let $(B_{\bot}^{\top}, \vee, \wedge, -, \bot, \top)$ be a Boolean algebra. Let $(U_Z^I, \cup, \cap, -, Z, I)$ be a universe algebra.

Definition
A class $C \in U^I$ is a member of the family of classes $U^I$ in the universe $U_Z^I$.

Comments
$-C \in U_Z$ is a member of the family of objects $U_Z$ in the universe $U_Z^I$.