 &gt; &gt; something like (ignoring the uniqueness clause
&gt; &gt; &gt; &gt; &gt; &gt; &gt; for brevity):
&gt; &gt; &gt; &gt; &gt; &gt; &gt;
&gt; &gt; &gt; &gt; &gt; &gt; &gt; (forall (?X1 ... ?Xn)
&gt; &gt; &gt; &gt; &gt; &gt; &gt;         (&lt;=&gt; (REL ?X1 ... ?Xn)
&gt; &gt; &gt; &gt; &gt; &gt; &gt;              (exists (?e)
&gt; &gt; &gt; &gt; &gt; &gt; &gt;                      (and (EVENT-TYPE ?e)
&gt; &gt; &gt; &gt; &gt; &gt; &gt;                           (ROLE-1 ?e ?X1)
&gt; &gt; &gt; &gt; &gt; &