David on The Doctor

“This extraordinary character who is everything at all times. It's continuously inspiring really, to get to play this mercurial, anarchic, extraordinary creature who gets all the best lines and gets to be the cleverest person in the room. I'm sure I'll miss lots about it, but I'll forever be proud to have been part of it, to be part of that history.”

“What we're asking is how the "replacements" could all be one in the same person. Non-Who fans might wonder, "Who cares?" But think about yourself at age ten. You acted differently, had a different worldview, a different personality, and different beliefs. As you learned, your brain structure was rearranged. In fact, gradually, your body completely replaces all of its cells using material and energy you ingested. Just like the Doctor, you regenerate; and you at ten is less like you now than that person across the room. How could you at ten and you now possibly be the same person? So our question about the Doctor's identity is very relevant. By answering it we can answer an important question about ourselves: How is it that we retain our identity over time?”

“According to K'anpo Rinpoche, each time the Doctor regenerates his cells are replaced and his brain structure is rearranged. Consequently, each Doctor has been quite unique. First was a crotchedy old man-a white-haired grandfather giving those young whipper-snappers "what for." By contrast, the Tenth was an exuberant young man-a great-haired lover, brash and impetuous. In between, he's been a clown (Sixth), a pleasant uncle (Third), a cricket player (Fifth), a scatterbrained jelly-baby-offering comedian (Fourth), and Moe from the Three Stooges (Second). But does regeneration make the Doctor, literally, a different person? K'anpo Rinpoche suggests the difference is merely metaphorical. He'll behave and look different, sure, but he won't be literally a different person-like twins are literally different persons. The Doctor still is the Doctor, regeneration after regeneration. If we saw the First and Tenth Doctor together, however, there'd be nothing to make us think they are, literally, the same person. They're more different than they're the same-more different then you and the person across the room. You and he or she aren't the same person, right? So how could each regeneration of the Doctor be, literally, the same person?”