楞伽阿跋多羅寶經註解 1.455

1.455

外道修行亦發邪慧，所見境界不知惟心發現，妄自分別有無，故言妄想見也。言分齊不通者，謂所現境界之相不能通達也。

When tīrthikas practice, they also generate perverse wisdom; regarding the realms they see, they do not know they are manifestations of mind alone, and falsely differentiate existence and nonexistence, which is why it is called "imagined views". "Their distinctions not penetrating through" means they are unable to thoroughly penetrate the marks of the realms that appear.