title: page() is not defined error message
body: <p>I am getting a <code>page() is not defined</code> error message from Firebug with the following Javascript. Why?</p>
  
  <pre><code>( function() {
      var page = function() {
          var min_central_width = 10;
          function minimumCentralWidth(val) {
              min_central_width = val;
          }
      }
  
      $(document).ready(function() {
          page().minimumCentralWidth(400);
      });
  
  })();
  </code></pre>
  
  <p>I am still new to Javascript. How can I avoid this?</p>