唯識二十論述記 2.97

2.97

述曰：此正申難，釋第三句頌「應障無」字。如以二手相擊觸時，東既非東等，云何左右手，展轉得相障，此由未曉不障所由。

Commentary: This directly presents the objection, explaining the words "obstruction would be absent" in the third line of the verse. For instance, when two hands strike and touch each other, since east is not east and so forth, how could the left and right hands mutually obstruct each other? This is because the reason for non-obstruction has not yet been understood.