首楞嚴義疏注經 2.483

2.483

若知五影因眚故見，終不執影是實有體，既無所見，能見何立？故無見咎。此約喻釋見無見也。

If one knows that the fivefold shadows are seen because of cataracts, one will ultimately not grasp that the shadows possess real existence. Since there is no object seen, how could a seeing subject be established? Therefore, there is no fault of seeing. This explains "absence of seeing within perception" by drawing upon the metaphor.