public static float hostility(Actor actor) {
    Plan p = null ;
    for (Behaviour b : actor.mind.agenda()) if (b instanceof Plan) {
      p = (Plan) b ;
      break ;
    }
    if (p instanceof Combat) {
      return 1.0f ;
    }
    if (p instanceof Dialogue) return -0.5f ;
    if (p instanceof Treatment) return -1.0f ;
    return 0 ;
  }