首楞嚴義疏注經 5.169

5.169

木、空、煙、火以理推窮非香生處，既來無因，去復何往？以何為香而馨我鼻？此別觀察香無生也。

Through rational investigation, wood, space, smoke, and fire are not the place where the fragrance arises; since it arrives without a cause, where does it go upon departing? By what is it made into fragrance so as to scent my nostrils? This is specifically contemplating that fragrance is unarisen.