title: If clause in Jess
body: <p>Could some one please help me using a if clause in jess, I know the simple sintax but I'm trying to use an &amp;&amp; operand so I can use two conditions, but nothing I try seems to work.</p>
  
  <pre><code>if((&lt;(?x ?y) &amp;&amp; (&gt;=(?z ?s)) then
    ....
  else
  ....
  </code></pre>