<?xml version="1.0"?>
<proof mode="standard" version="1.0">
 <goals>
  <goal t="#x(P(x) &amp; R(x))"/>
 </goals>
 <premises>
  <entry n="1" t="P(a) &amp; R(a)"/>
 </premises>
 <conclusions>
  <entry n="2" l="20" r="1" d="0" t="#x(P(x) &amp; R(x))  ;; That's all there really is to this rule."/>
  <entry n="3" l="20" r="1" d="0" t="#x(P(x) &amp; R(a))  ;; One need not replace every instance of the variable."/>
 </conclusions>
</proof>
