If you genuinely believe that[all good things flow from God], then you must be a dualist (which I doubt you are) because, by logical extension, all bad things must flow from somewhere else, which would make Old Scratch co-equal with God.C.S. Lewis answers this in Mere Christianity in the chapter "The Invasion."
Then Lewis attends to the charge that it's all a matter of taste. Which is Good and which is Bad? So he lays out for us some revealing comparisons and juxtapositions of the two forces, until we must confront the paradox here:
But the moment you say that, you are putting into the universe a third thing in addition to the two Powers: some law or standard or rule of good which one of the powers conforms to and the other fails to conform to. But since the two powers are judged by this standard, then this standard, or the Being who made this standard, is farther back and higher up than either of them, and He will be the real God. In fact, what we meant by calling them good and bad turns out to be that one of them is in a right direction to the real ultimate God and the other in as wrong relation to Him.
At the end, Lewis describes supernaturally what we see in the natural world [a connection I make in the link above]. Just as we see natural and man-made parasitics accompany all work or potential for work in the well studied science of thermodynamics, Lewis said this about the bad force.
I have a copy of Mere Christianity on my desk, and have been rereading it as I have had time over the course of the last few days.
I had just read the passages you quoted yesterday, in fact. ;-)
Great stuff, from one of the greatest minds of the twentieth century.
Regards...EV
Here, we have a switch between two different definitions of "good". Existence, intelligence, and will are "good" in the sense of "desirable" or "beneficial"; the distinction between the two powers posited by dualism depends on "good" in the sense of "morally upright". The two concepts can exist independently of one another -- one need only cite an example of a real, intelligent, and/or strong-willed advocate of an evil cause (e.g. Josef Stalin), or a fictional, stupid, and/or easily distracted advocate of a good cause (e.g. Inspector Clouseau).
In your commentary of yesterday The Good Don't Last Too Long, you took a substantial tangent to explain the difference between "good" and "right." As you can see here and at 199, and at steve-b's response at 198, more than a year ago he and I discussed this briefly.
Certainly your commentary complements ours. I was hoping this might add something to yours.
-Av