How to access private objects in a component's script?

In this question the OP asked about how to avoid exposing private objets to the outside in a component. I’ve been googling around and can’t find a way to do the opposite. Say I have the component below and I want to access privateObj from either my web page or a parent component. How can it be done using JavaScript and the Polymer API?

<polymer-element name="animating-element">
   <script>    
     var privateObj = {};

     privateObj.internalState = 0; 

     //private static method
     privateObject.setupState = function(polymerObject) {
        if(polymerObject.stateExposedToOutside == /* some conditions */) { 
           privateObject.internalState = 1;
        }
     }

     Polymer('animating-element', {
        stateExposedToOutside: 0,
        ready: function() {

          privateObj.setupState(this);
          this.animate();

        },
        animate: function() {

        }
      });    
   </script>
</polymer-element>