It's a fantasy, of course, because no such brainwashing is going to be possible, just as the fallen angels - if you look at line 607 - will be barred from drinking their fill of the river Lethe, forgetfulness is impossible.

当然这是一次幻想，因为这种洗脑,根本就不可能实现，就如同那些堕落天使一般,如果看第607行7,他们被禁止喝忘川之水，遗忘是不可能的。

耶鲁公开课 - 弥尔顿课程节选