title: Cannot understand Prolog operator precedence error
body: <p>I am trying to create a knowledge base. My problem has <code>gate/1</code> and <code>terminal/1</code> and I have defined the following rule:</p>
  
  <pre><code>gate(G) /\ terminal(T) :- (G \== T \== 1 \== 0).
  </code></pre>
  
  <p>What I am trying to say is that: "If there exists a gate G and a terminal T, then that implies that G is not equal to T is not equal to 1 is not equal to 0.</p>
  
  <p>I get the following error: <code>ERROR: c:/noob.pl:140:0: Syntax error: Operator priority clash</code></p>
  
  <p>I don't even know if I am using the correct operators.</p>