Lucas reported after the first Star Wars movie "A New Hope" that he wrote a story for children.

It's easier to divide the world into "good and evil" "dark and light" because there's a natural tendency in all of us to think in dualistic polar opposites.

But within each good or "light" person there are elements of darkness. And a person dwelling in the dark has light. Even Luke says "I feel the good in you father, release your hatred." or something to that effect. The "light" and the "dark" of Star Wars are defined by war, conflict, killing / murder and death.

The battle between light and dark is finding the balance in each of us, IMO. Balance is the third force and a way out of violence - a way of reconciling each side to move beyond the conflicts of good vs. evil.

Here's a link to a piece about the reconcilers of the world - those that follow the path of balance: https://medium.com/know-thyself-heal-thyself/forging-peace-772129ee3c33