So, according to Yeshayahu 45:7, G-d ” forms light and creates darkness” and “makes peace and creates evil”. The word “creates” used for “darkness” and “evil” here is the same appearing in Bereshit 1:1. In Bereshit 1, G-d then forms light and separates it from darkness. Perhaps, by analogy, good is separated from evil?
I may be wrong on this. What are Judaism’s views on the origin of good and evil?