GeoAgent in geography,  the PolAgent
in politics, and the EcoAgent in economics.  Working together, they can answer
queries  that no one of them could have answered alone.</p>
      <p>For example, suppose a user asks the GeoAgent for "elected heads
of government of countries  north of the equator".  This might be represented
as:</p>
      <p>
<font face="Courier">(#$and<br>
&nbsp;&nbsp;&nbsp;(#$headOfGovernmentOf ?x ?y)<br>
&nbsp;&nbsp;&nbsp;(#$hasAttributes ?x #$Elected)<br>
&nbsp;&nbsp;&nbsp;(#$northOf ?