成唯識論述記 2.501

2.501

述曰：比量可知，若非此處色合時，餘處色不合，即色等法應互相遍，以此處色合時，餘處色亦合，此處色即餘處色故，一一色等應互相遍，隨彼虛空其量遍故。

The Commentary states: The inference is readily known. If it were not the case that when conjoined with form in this place it is not conjoined with form in other places, then dharmas such as forms would mutually pervade each other: because when conjoined with form in this place it would also be conjoined with form in other places, so form in this place would be identical to form in other places; thus, each form and so forth would mutually pervade, corresponding to the pervasiveness of the measure of that space.