When to use magic methods in PHP?

Question

A friend and I have been bickering on skype for a while now about when magic methods like __get is useful.

For example, say you've got a public/private array:

class test {
    private $array = ['test' => 'blah'];

    public function __get($name) {
        return $this->array[$name];
    }
}

is this a proper application of magic methods? We are arguing because on the php.net page for magic methods it says for 'inaccessible members/properties'. I am of the belief that this means private variables and while it can be used to array things inside of arrays without accessing the array explicitly, that isn't the intended use.