金剛經纂要刊定記 7.49

7.49

此言下。揀異大小。大乘用觀假想分別起其慧數，破析彼色一一分析至於極微，二乘天眼所不能見，此則細末之極不可破析，名極略色。

From "These words..." onward differentiates the Mahāyāna from the Hīnayāna. The Mahāyāna employs contemplation, using conceptual imagination to give rise to the mental factor of wisdom, analyzing that physical form piece by piece down to the paramāṇu, which the heavenly eye of the two vehicles cannot see; this is the ultimate limit of fine division that cannot be further analyzed, called "extremely summarized form" (parama-saṃkṣepa-rūpa).