yāvatā tasyāvastutayā hetubhir na kiñcitkriyata iti kathaṃ hetumattā bhavet / prayogaḥ yadavastu na tat kasyacitkāryam yathā śaśaviṣāṇam
However, since it is a non-entity, causes cannot do anything to it - so how could it have a cause? The formulation is: "Whatever is a non-entity cannot be an effect of anything - like a hare's horn."