public function hasErrors($includeNested = true)
    {
        if (Hash::filter($this->_errors)) {
            return true;
        }

        if ($includeNested === false) {
            return false;
        }

        foreach ($this->_properties as $property) {
            if ($this->_readHasErrors($property)) {
                return true;
            }
        }

        return false;
    }