Вызов функции-члена allow () для не-объекта - авторизация

Я использовал этот учебник: http://book.cakephp.org /2.0/en/tutorials-and-examples/blog-auth-example/auth.html

Чтобы построить мою первую форму / создать пользовательское приложение, но это не удается с сообщением об ошибке:

Fatal error: Call to a member function allow() on a non-object in /home/public_html/cake/app/Controller/UsersController.php on line 18

Это ius 18-я строка:

$this->Auth->allow('add', 'logout');

Вышеупомянутая строка является членом функции:

public function beforeFilter() {
    parent::beforeFilter();
    $this->Auth->allow('add', 'logout');
}

Весь мой UsersController.php :

Auth->login()) {
            $this->redirect($this->Auth->redirect());
        } else {
            $this->Session->setFlash(__('Invalid username or password, try again'));
        }
    }

    public function logout() {
        $this->redirect($this->Auth->logout());
    }

    public function beforeFilter() {
        parent::beforeFilter();
        $this->Auth->allow('add', 'logout');
    }

    public function index() {
        $this->User->recursive = 0;
        $this->set('users', $this->paginate());
    }

    public function view($id = null) {
        $this->User->id = $id;
        if (!$this->User->exists()) {
            throw new NotFoundException(__('Invalid user'));
        }
        $this->set('user', $this->User->read(null, $id));
    }

    public function add() {
        if ($this->request->is('post')) {
            $this->User->create();
            if ($this->User->save($this->request->data)) {
                $this->Session->setFlash(__('The user has been saved'));
                $this->redirect(array('action' => 'index'));
            } else {
                $this->Session->setFlash(__('The user could not be saved. Please, try again.'));
            }
        }
    }

    public function edit($id = null) {
        $this->User->id = $id;
        if (!$this->User->exists()) {
            throw new NotFoundException(__('Invalid user'));
        }
        if ($this->request->is('post') || $this->request->is('put')) {
            if ($this->User->save($this->request->data)) {
                $this->Session->setFlash(__('The user has been saved'));
                $this->redirect(array('action' => 'index'));
            } else {
                $this->Session->setFlash(__('The user could not be saved. Please, try again.'));
            }
        } else {
            $this->request->data = $this->User->read(null, $id);
            unset($this->request->data['User']['password']);
        }
    }

    public function delete($id = null) {
        if (!$this->request->is('post')) {
            throw new MethodNotAllowedException();
        }
        $this->User->id = $id;
        if (!$this->User->exists()) {
            throw new NotFoundException(__('Invalid user'));
        }
        if ($this->User->delete()) {
            $this->Session->setFlash(__('User deleted'));
            $this->redirect(array('action'=>'index'));
        }
        $this->Session->setFlash(__('User was not deleted'));
        $this->redirect(array('action' => 'index'));
    }
}
?>

Почему это происходит?