Who is the Doctor?
This is a question that has been asked by many. More often than not, it is answered with a shrug of the shoulders, and a repetition of the word. The Doctor is just that, the Doctor.
Another question, though not always asked, is what is the Doctor?
Depending on who and when you ask, the answer may be that he's just some guy. It may be that he's an alien, the last of his kind, or one of many like him. He's always running, some will say. He's a force of nature, a legend, the personification of chaos itself.
They will tell you he is a good man.
And why shouldn't they? It's a story that happens again and again, throughout all of time and space, that when people are suffering the Doctor will be there to help thim. Children grow up listening to their parents tell them at bedtime of this mysterious hero that will be there for them whenever things seem hopeless.
They say he hates violence, that he won't ever touch a gun. They say he's a genius with a screwdriver, and that evil runs at the sight of him.
They can't tell you who he is, all they can do is praise the work he's left behind.
Somewhere out there lives a man in a blue box. If you ask him what the Doctor is, he will tell you that he is someone who saves people. He will tell you that the Doctor isn't a hero, that he shouldn't be worshiped, but he does save people when he can. That's what a doctor does, right? It's the same concept, sans the medical aspect.
He will tell you that the Doctor is humble. The Doctor is kind. The Doctor harms no one.
The man who will tell you this is known as the Oncoming Storm. The Approaching Dark. The Time Lord Victorious.
He walks a trail of fire wherever he goes, and his eyes, they burn with fury. A vengeful deity that rains destruction down on those who hurt him, who hurt anyone he cares about.
This man knows no allegiance, and he is feared by both good and evil alike. People write songs about him, foreboding lyrics of warning. Any who cross his path risk being left as embers in his wake.
The truth of the matter remains unspoken, a secret hidden so deeply that only the universe itself knows. It's stitched into the very fabric of reality, a fact that, though unseen, is no less fact.
Who is the Doctor, you ask.
The universe will tell you that the Doctor doesn't exist. The Doctor is the character of a story, a flawless protagonist that would do no wrong, someone who protects others out of the goodness of his heart, someone who wouldn't raise a hand to strike the worst of his enemies.
What is the Doctor?
The Doctor is what the man in the box aspires to be, but never will.