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The concept of self image was far more fluid to a Time Lord than a human, releasing on some matters but utter hell in others. It was like losing your favorite shirt multiplied by his own lifespan. Granted, the Doctor always felt that his current body was definitely superior to the previous, despite what he would think several regenerations later. He figured it was some sort of survival instinct, though that was probably too severe a phrase.

But still, to look in the mirror and recognize the self was human, to look and recognize the self-that-may-change-into-another-self-tomorrow was Time Lord. In the lulls between companions and things exploding inside or outside of his ship, he'd find himself gazing at his reflection in the mirror, seeking signs of those who had been 'self' years past. Other times it was far more trivial; what would he look like with curly hair again? And he always had liked that hat…

And the Doctor would grimace and think "That's not me." But it had been. He was the same man, same memories, same goals and desires and yet what he deemed what was 'him' was as changing as his own face.

The age thing had always been a bit of a throw off, too. He'd never been able to control what he'd become when he regenerated, but as the years and bodies went by he wondered if their was a subconscious element to it. The Doctor was old, but at some point the got tired of being old, and for a time he found himself getting younger with each new face. Except there'd been a bit of fluctuation, so he'd never been able to establish a definite pattern. He frustrated himself sometimes.

And speaking of patterns, you'd think that a regenerated Time Lord could maintain at least a trait or two recognizable in all forms. How many times in his youth had he wandered by some of his best mates and neither of them recognized the other? You'd think they'd evolve some way over that at least. Masters of Time and Space but family reunions were impossible.

Nametags, maybe? 'Hello, my name is: The Doctor.'

Possible, it would certainly save him the effort of introducing himself every time someone stuck their head into the TARDIS. Even though there was a certain thrill of it. But then he'd certainly recognize the Master every time he'd pop up and know to start looking for signs of another bizarre plan to rule the universe or whatever. That last one had been pretty effective, though…best not think on that.

On the other hand, he knew there were advantages to regenerations (aside from the not dying part). The same face, hands and gestures after nine hundred years? How dull. And how many times did he just happen to need to make a stop in the twenty-second century, and then he just happened to trip across dear Susan? Sometimes it was nothing more than a glance in passing, others he managed to pass simple pleasantries. Every new regeneration, he found time, because she wouldn't know him. Because he didn't want her to see what her old grandfather had become. And it was getting increasingly difficult not to bump into his previous selves doing the same thing.

When traveling through time and space, change was best, even if it meant changing your concept of self every few years. Stiff and unchanging wouldn't survive in the flux of timey-wimey stuff, something the Time Lords themselves seemed to forget. And they wondered why he was always buggering off.

Survival it was, then. And sanity. Sanity was definitely a big one.

So here he was, ever changing, flexing, ready to bend in the flux of time because he could do nothing else. Self meant nothing like this without anything to relate it to. What was he? The Doctor, and he was a Time Lord. But was that enough? He was the change of an unchanging people, and now they were gone and he was alone. Where was the comparison? It was merely an idea of self, but nothing solid he could grasp anymore, if he ever could.

But there was the TARDIS.

His ship, his beautiful, groaning ship. He knew her, the TARDIS was definite, and by relation, gave his elusive self a definition. But even it changed, by definition he changed and therefore so did it. Long gone were the white walls and sterile floor, the Time War had changed him and ship both; it was now dark and filled with holes and hidden nooks. Self and ship. Ship self. The cycles and regenerations went on. Everything must always change and self with it, and when this was no longer possible, self ceased to be in any form.

Goodbye Gallifrey.

And yet, he came to realize there was one thing that he could find steady, truly unchanging in all the universe, one he had control over. Very time the Doctor stepped out of the TARDIS he'd look back and there would be his blue police box. He didn't even bother to try to fix the chameleon circuits anymore.

The self and its image would change and change again, and so would the universe. But the Doctor had one definite in his long life, the image of home that was not a planet.

The definite of a flying blue box.