The nature of evil?

[loostudent]

Evil causes “sin”, sin means error, perhaps evil is just the mistake of perceiving separation.

Sin (moral evil) is not the same as error (natural evil). Sin (and goodness) is intentional/chosen. But I agree. This is the veiled perspective that makes this choice even possible. Without veil unity would be so obvious that it would be impossible for someone sane to come up with real separation and sin.