1 ?e ?x)
&gt; &gt; |                           (Member2 ?e ?y)
&gt; &gt; |                           (Member3 ?e ?z)
&gt; &gt; | )       )    )       )
&gt; &gt;
&gt; &gt; 2.
&gt; &gt;
&gt; &gt; | (forall (?x ?y ?z)
&gt; &gt; |         (&lt;=&gt; (TitanicTrio ?x ?y ?z)
&gt; &gt; |              (exists (?e)
&gt; &gt; |                      (and (Donald ?e)
&gt; &gt; |                           (1st Nephew ?e ?x)
&gt; &gt; |                           (2nd Nephew ?e ?y)
&gt; &gt; |                           (3