<?xml version="1.0" encoding="UTF-8"?>

<RuleML
xmlns="http://www.ruleml.org/0.9/xsd"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://www.ruleml.org/0.9/xsd http://www.ruleml.org/0.9/xsd/datalog.xsd">

<Query>

      <Exists>
        <Var>merchant</Var>
        <And> <!-- Or also allowable, or directly an Atom, or a nested Exists -->
          <Atom>
            <Rel>buy</Rel>
            <Var>person</Var>
            <Var>merchant</Var>
            <Var>object</Var>
          </Atom>
          <Atom>
            <Rel>keep</Rel>
            <Var>person</Var>
            <Var>object</Var>
          </Atom>
        </And>
      </Exists>

</Query>

</RuleML>
