AFAIK Watson doesn&#x27;t generate Prolog. It does use Prolog rules:<p>&quot;Specifically, decomposition for Puzzle questions is performed by matching manually developed Prolog rules against the question’s predicate-argument structure to identify its subparts.&quot;,<p>&quot;Relation detection patterns are written in Prolog and apply unification pattern matching over PAS&quot;<p>&quot;Most of our rule-based question analysis components are implemented in Prolog&quot;<p>(All from the IBM system journal issue on Watson).<p>I&#x27;m pretty sure I&#x27;ve read all the published papers on Watson (the QA system). It&#x27;s possible I&#x27;ve missed something, so a citation would be great if I have.