the ying and the yang make a circle
the good and the evil make a person
the god and the devil make earth
the seratonin and the dopamine make endorphine
the id and the superego make the ego
the matter and the energy of the universe make the boundaries of the universe
the good guy and the bad guy make a good movie
God and the Devil didn't make the earth. It is told that God alone made the Earth. A human is not made of Good and Evil, it is made of Good but turns evil. A baby is not born evil. The universe has no boundaries or limits, it is endless, choose what you believe about it thou. Ying and Yang do make the circle, if you believe in the Ying and the Yang effect. But the Yang can overwhelm the ying at any moment and vis versa. Their is much more about the universe that will remain unknown. At least you try. But I think you need to keep thinking cuz it isn't that simple. Wish it was tho.

Oh and yes the good guy and the bad guy do make for a good movie.