Answer:
Good and evil
Step-by-step explanation:
The text says that the right-handed twin lives in the sky-world. Only what is good can live in the sky so we can conclude that the right-handed twin represents the good and the good things that are present in the world.
Soon after, the text informs that the left-handed twin delights with the sounds of war and suffering. Only a cruel and sickly person would delight in something so bad in humanity, and this shows that the left-handed twin represents evil.
The text passes the information that the two twins complete themselves in ruling the world and taking care of the affairs of men. This shows the balance between good and evil in the universe.