Hmmm, interesting, is never noticed that before. If theres light, dark and a combination of the two, (balance) perhaps it is meant to represent force null? I don’t know, just a half baked thought

What is force null? Also, I understand why the other hands mean what they mean. The dark side is usually associated with anger. When we are angry, we often form a fist with one of our hands. For the light side, representing probably the selfless, a relaxed hand is a helping hand. As for balence, the hand isn't relaxed nor tight, it is something in between. I find it interesting that the forth hand gesture is positioned in between dark and either light or balance. As I stated before, I don't know what null means, but the forth hand gesture is a pointing hand, something we make when we try to be specific or to target something.