Prompt: Well here we are again/ It's always such a pleasure (Want You Gone, Portal 2: Songs to Test By)

They were eternal, the pair of them. Light and darkness, yin and yang.

A strike and a parry.

A parry and a strike.

It was balanced, perfectly keeping the scales at zero, never dipping in the slightest.

Yang was chaos and war and the tears of confusion. He was the dark corner in the bedroom and the alleyway with a flickering streetlight and the monster under the bed. When he looked at them he saw their greed, their envy, the vices of seven billion weighing on the scales.

Yin was order and peace and the warm glow of satisfaction. He was the light that banished the shadows and the shoulder to cry on with promises of, "Everything is going to be okay." He saw them not for their missteps, but for their triumphs.

They would meet occasionally, admiring each other's new regeneration look for the new age. They would compare the world, question the peoples' progress, wonder about their purpose.

This time it was a small London café during an air raid, the streets dark and empty, not a flicker of light in sight. Yang liked that, the shadows were his domain, but to Yin it was a sort of joke. Yang, who loved chaos and war, was protecting the people. A paradox, of sorts.

The inside of the café was even darker than outside, but perfectly positioned as if it were in business. A cup of coffee was still steaming on one of the tables; the customers must have abandoned their meal to head to the shelters. Yang took a seat by the window, and Yin followed suit, looking through the dusty glass at where the people should have been, crowding the streets with their everyday bustle. Barren, as Yang liked it.

"What do you think of the world, Yin?"

It had been the same question for eternity, since the first ray of sunlight lit the surface of the earth.

"As it should be." Yin answered, like he always did. Since the first ray of sunlight lit the surface of the earth, as it should be.

No thanks to Yang, of course. He always tried to meddle, to tip the scales his way, preying on the weakness of the humans, never ceasing until he was the seed of doubt in seven billion minds. Yin knew it was fruitless, however. One could never come out on top. That was their purpose, wasn't it?

"Who are you supposed to be?" Yang tipped his head towards Yin, who glanced down at his getup.

"I appear to be some sort of reporter. A journalist, perhaps. How about you?"

Yang threw back his head and laughed. "Me? I'm an earl, I do believe. I have racing dogs and play croquet and am lavished with riches. Shame I can't actually be part of it."

"Part of what?"

"Why, the world, of course. Don't you think it would be quite the adventure? A bit of glamor, dashing around and doing this and that, worrying about the most minute of problems. To taste their food and see their sights as part of the world. Their lives are dreadfully short, though. Often drear."

"Delightfully drear."

Yang frowned, straightened his lapel. "So are our lives. Have you ever considered us, Yin?"

"Often, in fact."

"You see what I mean. I understand we are opposites, always at war, but what can we do then? If I attack you're there to deflect the blow. Why do we bother?"

Yin pondered this. "What if we do nothing?"

A scoff. "The humans would fall into disrepair. Right now, even, a war to keep them from progressing too fast. They're getting too big for their britches, keep them occupied a bit and you forget all about science unless you can weaponize it."

"You think they could stand on their own?"

"The opposite. How convenient - opposite."

Yin smiled as the first bomb crashed into London, the shrapnel tearing through the city's heart. Yang's smile grew to mirror Yin's and the first human sound echoed from the ghost of the city. Screams.

"Keeps them occupied, like I said. Bit of a population thinner. Don't give me that look, it's better if you're not attached to them. Just a few prods here and there. You know when, don't you? A tiniest nudge in the right direction. That feeling you get, that small subtle feeling, and you move."

Yin knew summons, he knew when he had to steer the humans along, but not like cattle, as Yang thought. Yang was the whip on the horses' backs. Yin preferred to think of himself as a bit.

"How have you steered the world, Yang?" Yin asked dryly, the shouting of the humans prickling at the back of his mind.

"Easy, really. The thoughts, their minds are like code. Genes, genetics. Splicing genes, inserting data. Sticking a thought in there is just as easy as that. They're not to gene splicing yet, are they? Like I said, drear."

Yin, for the first time, felt guilty. It was true. He liked to think the humans were strong and powerful, who could overcome the hugest opposition when he really could slip in an idea that could change them entirely. Powerful, but maybe he and Yang were just too good at their jobs. He was currently tapped into the mind of Winston Churchill, bringing ingenious strategies to light. They were already in his mind, just shuffled back a bit into the darker recesses. Yin saw potential where Yang saw victims. Yin didn't need to invent, he could simply find the good in people. Yang spawned spite.

"I could always just make it appear in a young, budding scientist's head. But that's your job, isn't it? You had that job with Isaac Newton ages ago, the apple was a nice touch. Just... Make it apparent. There's no need to dig around in their trunks of minds, full of old memories and useless facts and stock exchanges, rooting about for what you want to find. You can create such wonderful things, if I can create terrible ones. And can I make terrible ones."

He had been sorely tempted for years. Things that were so apparent to him the humans were stumbling over, fumbling about in the dark for something they just couldn't reach. It would be so simple, just with a brush of an idea, the simplest gift...

But he and Yang were opposites. He couldn't if he tried.

Yang knew it was fruitless, but tried anyways. Every time.

"Guess you got the worse end of the deal. I get to have fun and you get to clean up my mess."

Yin would have objected, seeing as Yang did relatively little to change history, but if they were opposite in all they were opposite in scale. Yang loved the small tortures, the prodding that drove you insane, and Yin steered humanity to its checkpoints. And what Yang found fun Yin found despicable.

Always opposites.

"Ever wonder about the course? I never really see it, but you get the big picture. Where we're heading. They're heading, of course. I bet it's going to be abysmal, some fate placed upon themselves, that they caused, too much pollution or something. That will be a fun time, hurrying into the politicians' minds, whispering in their ear. You'll be fussing with the course, but you know that it's correct, that you can't save them. What will happen to us? Drifting in space, perhaps, wondering about our brief time on earth forever."  Yang frowned, turning his fork over in his fingers. "How do you tolerate it?"

"The job? Maybe not as flashy as yours, but it's satisfactory. Why?"

"No, no, not the job. Humans. I look at them... They're so feeble, like little bright candles that burn down into a clod of wax. Not remotely interesting or exciting. How can you care about them? Their minds collapse like cardboard, they follow my every wish. Can you imagine being so powerless?"

"Humans are like candles, but not like how you think." Yin tilted his head. "Have you ever watched fire? I assume so, it's part of your job. Really, truly watched it burn? It's captivating, and so bright. Fire and flame and a million colors blazing up, consuming all. That's what humans are. They're bright as tongues of flame, with their vivacity and their boldness, but also in their shy smiles that speak volumes. Have you seen them? Covered in every color, draped in flame. They are short, but they are brilliant. You and I, we're drab. Conversing in cafés, pondering life when they're inventing life. They're making life. They change it every day!

So, no, I don't see them as fodder for my whims. I don't see wax, molded for my purposes. I see fire."

Yang shook his head, smiling. "You're so naïve. How bright do you think humans really are? Look at the average joe. He drinks coffee every morning, wears the same gray suit, and moans about how if he had only done better in school he could have a satisfactory job, a relationship. If he's a color, he's gray, the bland gray that you see when you ride the bus to work. Dull and dragging. How is he fire, as you say?"

"The average joe is the foundation of the human race. Do you see activists and sports stars filling the streets? The majority is what it takes to make a difference, and I care about the majority. A dozen candles can light the largest bonfire, even if they're dying out themselves. They see the light. You use war to snuff out candles. The end of the war is my beacon of hope, the bonfire to light a dying generation. You'll see."

Yang snorted. "You're no fun to talk to anymore. Starting to sound like one of them. Maybe I should pick one up as a pet, see what he thinks of things. 'Shall I put this idea in Mister President's head, Jerry?' 'Why, I think that's a swell idea, sir.'"

"That's where you're wrong. Humans aren't pawns."

Shell-shocked, the city rumbled under their feet. Wailing alarm sirens blasted their message into the air, all light extinguished. Gone. A war to still the generations, a war full of toy soldiers. Pawns.

"Then why are we playing chess?"