So $D \isin C \equiv D \le C$.
}
-\subsection{Totally Foreign Contents}
+\subsection{Totally Foreign Ancestry}
Given conformant commits $A \in \set A$,
$$
\left[
\proof{
Consider some $D \le C$. If $D = C$, $\isforeign{D}$ trivially.
If $D \neq C$ then $D \le A$ where $A \in \set A$. By Foreign
-Contents of $A$, $\isforeign{D}$.
+Ancestry of $A$, $\isforeign{D}$.
}