Author's Note: I suppose that this is technically an AU, since it takes place in the Year That Never Was and the Doctor in my head is the un-artificially-aged version of Ten. But I think it offers a few interesting observations of how the Doctor views himself.
Enjoy!
Intermezzo
The Doctor sat with his back to the bars, fingers tapping to the rhythm of a Yuletide song they had heard on Corax 5. The beat was a bit catchy, but the lyrics just seemed wrong now.
There might not be peace on Earth or goodwill to men ever again, now.
No, he told himself sharply. It was no good indulging in that kind of thinking. He believed in Martha. She would come through. It was her time to be the hero—to be the hero he never could be, because of what he was, what he'd done.
Today, she was his hero.
"You killed them all." The voice came without preamble, a voice which he could have done without hearing.
"Good afternoon to you too," he drawled with a sharp edge under his voice. He considered saying go away, but the Master would never listen to that.
"You just… killed them all."
"I had no choice, Master. You don't know what they would have done—what we would have become." Had I become it? That was the all-consuming question.
"Did you stand above it all, removed, and watch them burning? Oh yes, I've heard the stories," the Master continued. "How did it feel to choose death for them?" The Doctor stood, slowly, controlled fury making his posture tense, every muscle in his body like a tightly-coiled spring.
"No one has the right to choose death for another person, Master. No one." he said through his teeth. The Master ran a finger around the curve of his ear, flicking the dead skin out from under his nail.
"I just…" He smiled mockingly.
"What?" the Doctor asked, guardedly.
"It's ironic, isn't it? I was their perfect soldier, and I ran when Arcadia fell. But you stayed until the very end. You even ended it."
"Stop it."
"It turns out you were a better soldier than me."
"I said stop it!"
"The perfect soldier, even."
"Shut up, Koschei!" the Doctor shouted, clapping his hands over his ears. The Master grinned.
"Oh, I've done it now. We're using home names, aren't we? Don't think that I won't use yours. Do you even remember yours?" With an obvious effort, the Doctor turned away.
"You should know. You picked my missions, remember? Always trying to control my life. In a way, Koschei, you made me what I am now. My team died, remember? And then they told me I couldn't see my family any more. My wife, my sons and daughter—all of that gone. I was just lucky I found Susan. I'm surprised I ever found out. She was born long after the order that I wasn't going to see them any more. I lost everything that mattered long before the Time War, Master."
"Oh yes, and then you killed them all again," the Master drawled. There was silence. "You always did have a bit of a cruel streak." he goaded. The Doctor looked up sharply.
"Why did you think I chose this name?" he said in a low voice. "I didn't choose it because I thought it sounded nice. I chose it because I hoped I could live up to it."
"And how is that working out?" the Master asked.
"No, you're right," the Doctor continued. "We're exactly the same, you and I. Except for two things. I choose when to stop. You don't know how to stop."
"And what's the other thing?" the Master said, thumping the bars in that irritating pattern of four beats.
"The reason why you always lose? It's necessity, Master."
"I don't follow." The Master smiled.
"You lack conviction. You don't do this because you have to, because the other option is unthinkable. No, you do it because you think it's fun!"
Silence.
"You talk just to hear the sound of your own voice," the Master accused, and left the room.