With the other people out of the room, the visages of both men changed, slightly. Both usually had cheerful countenances, although the Doctor also had a manic element to him that Captain Sheridan lacked. But they both looked more somber.
"The war that has come up is going to be very hard. I don't know if you have gathered exactly what is going on, but I will have to end up fighting several wars, one against the Shadows, one against our own government at home...I have to admit, I can't even comprehend the power of some of these groups. It seems like you could help us."

"I'm sorry, Captain, I understand what your struggle is like, but I can't stay. I have other...appointments."

"You are a time traveler? Couldn't you stay here as long as you wanted?"

"Time doesn't work that way."

"And why not?"

"Captain, do you know what a Calabi-Yau surface is?"

"No."

"I've known since I was eight. I am over a thousand years old now. Time travel isn't an easy thing to explain."

Sheridan settled backwards into his chair. "I could...keep you here."

The Doctor smiled: "You mean you want to draft me into this war of yours?"

"It could help so many people."

"Captain, you won't do that. For two reasons. First, you know this station is a waypoint for travelers, and that if you start using people here for your own agenda, it will ruin your reputation. And your conscience. But just to make things easier for your conscience, do you really think you can keep someone captive who the Shadows and the Vorlons are afraid of?"

The Captain's face fell, but he returned with another question.

"What was that bit with Kosh about, you seemed angry with him. The Vorlons are our allies."

"Captain, you must have studied enough military history to know how often alliances are an equal partnership."

"Care to explain that for me any clearer?"

"Why don't you ask Kosh? A little simpler than asking me, isn't it?"

"It is extremely difficult to get a clear answer out of Kosh."

"My point exactly" The Doctor answered, with a finality.

Captain Sheridan let out a long, impatient sigh.

"Do you not care that this war could kill billions of people?" Captain Sheridan regretted the question as soon as it was out of his mouth, because he saw a look of mingled rage and sorrow flit across the Doctor's face.

"Of course I care. I care very much.

"I am a Time Lord, Captain. That means that I can see time. What can happen, what might happen, and what must or mustn't happen.

"But even if I wasn't a Time Lord, I know a thing or two about history. In times of oppression and conflict, even if help is given, it is the people who value peace and freedom who must put the effort into fighting the war. If I could magically wave my sonic screwdriver and make this war go away...you would be back in the same situation soon enough. Maybe in one year, maybe in five or ten. In the process of fighting this war, you can put together something bigger than the war itself. And that is why I wasn't meant to come here to help you.

"Besides..." The Doctor's eyes lit up, he had thought of another mysterious connection. "I will talk to a friend of mine. A bit like me. You will like him. Well, eventually."

Sheridan stared at The Doctor. Although the last part was unclear, he saw the truth of the Doctor's words. He sighed heavily, knowing that his hopes of a quick fix to his situation were disappearing. But after this much time on Babylon 5, he knew that there were no magic wands. Or screwdrivers.