ion for
&gt; &gt; &gt; &gt; &gt; &gt; example).  As each record is pulled into the common DB it's
&gt; &gt; &gt; &gt; &gt; &gt; checked against
&gt; &gt; &gt; &gt; &gt; &gt; the constraint
&gt; &gt; &gt; &gt; &gt; &gt;
&gt; &gt; &gt; &gt; &gt; &gt; (=&gt;
&gt; &gt; &gt; &gt; &gt; &gt;    (and
&gt; &gt; &gt; &gt; &gt; &gt;      (instance ?X Employee)
&gt; &gt; &gt; &gt; &gt; &gt;      (birthTime ?X ?BTIME)
&gt; &gt; &gt; &gt; &gt; &gt;      (deathTime ?X ?DTIME))
&gt; &gt; &gt; &gt; &gt; &gt;    (greaterThan