妙法蓮華經玄義 8.83

8.83

二、譬頗梨、如意，兩珠相似，形類欲同，而頗梨但空，不能雨寶。如意珠，亦空亦雨寶。頗梨，無寶以喻偏空；如意能雨，以喻中道，此就有無合為俗，簡偽顯真。今經體同如意也。

Second, the analogy of crystal and the wish-fulfilling jewel: the two jewels are similar, their forms and kinds almost the same, yet the crystal is merely empty and cannot rain down treasures. The wish-fulfilling jewel is both empty and rains down treasures. The crystal's lack of treasure illustrates biased emptiness; the wish-fulfilling jewel's ability to rain [treasures] illustrates the middle path. This combines existence and non-existence as the conventional to distinguish the false and reveal the true. The substance of the present sūtra is identical to the wish-fulfilling jewel.