This is a story originating from the Native Americans with loads of wisdom.  It’s much easier to “feed” the dark wolf, because it takes effort to resist that temptation. “Feeding” the white wolf takes more effort, but the rewards are so much more.

I think one has to acknowledge that they have a dark side in order to recognize when one is in trouble and in danger of “feeding” that dark side…it keeps one humble….making it more difficult to be self-righteous (which I see a lot of with the “holier-than-thou” crowd now deep in politics.)