大般涅槃經義記 5.202

5.202

第五句中，「心若常者亦復不能分別諸色」以多分別破心定常，常則不動，安能分別種種諸色？「所謂青」等出所分別。

In the fifth clause, "If the mind were permanent, it also could not distinguish diverse forms" refutes the idea that the mind is definitively permanent by pointing to its manifold distinctions. If it were permanent, it would be unmoving; how could it distinguish various kinds of forms? "Namely, blue" and so forth indicates the objects distinguished.