Assertion: isometry | /r/CapableOf | fix $r$
Facets:
Source sentences:
text: If $p$ and $q$ are arbitrary, let $\gamma$ be a minimizing geodesic from $p$ to $q$, and let $r$ denote the midpoint; an isometry fixing $r$ and reversing the direction of $\gamma$ exchanges $p$ and $q$.)