首楞嚴義疏注經 3.113

3.113

「阿難！汝又嗅此爐中旃檀，此香若復然於一銖，室羅筏城四十里內同時聞氣。於意云何，此香為復生旃檀木？生於汝鼻？為生於空？」

"Ānanda! You also smell the candana in this censer. If only a single grain of this incense were burned, within forty li of the city of Śrāvastī all would simultaneously smell its aroma. What do you think: is this fragrance born from the candana wood? Is it born from your nose? Or is it born from space?"