Science Fiction & Fantasy Stack Exchange is a question and answer site for science fiction and fantasy enthusiasts. It only takes a minute to sign up.
Sign up to join this community
Near the end of Deep Breath, the Doctor says
I'm the doctor.
I have lived for over 2,000 years,
And not all of them were good.
Wasn't Matt Smith's Doctor just above a thousand years old? Did he pick up another thousand years in Trenzalore, or is this something else? (Adding up the years of all the "time can be rewritten" existences that the Doctor remembers but hasn't exactly lived through, perhaps?)
Yes, he spent 900 years on Trenzalore (which I thought was utterly ridiculous, but there we go).
When Clara returns the first time:
The Doctor to the TARDIS: Well. Where have you been for three hundred years?!
The remaining six hundred are not explicitly stated in the script for Time of the Doctor, but it has become the generally accepted number thanks to non-television canon media.
Presumably, those years were indeed accumulated during the Siege of Trenzalore as you say. There were two massive time gaps in that episode; the first spanning 300 years and the second spanning an unspecified-but-certainly-very-long period of time. The tie-in novel "Tales of Trenzalore" states that he spent a total of 900 years on the planet, but as that story also depicts him with a missing leg (a development that was cut from the original script for "The Time of the Doctor"), the relevance of that book is debatable.
However, the prevailing truth is that, after "Time and the Rani" (in which he had to be 953, as he used the fact that he and the Rani are the same age in order to deduce that her age-based password was that number) at the earliest, the Doctor has simply lost track of what age he is. He states as much in "The Day of the Doctor", and if, for example, we were to factor in the alleged 600 years that the Eighth Doctor spent on the titular planet in the Big Finish audio drama "Orbis" (although even in that story, he states that he doesn't always count years the same way and that he sometimes adjusts his age count based on wherever in the universe he is in at any given time), then that would already make him over 1,000 by the time of his Eighth incarnation, which thoroughly contradicts his Ninth incarnation's assertion of being 900 years old (although "Time and the Rani" already accomplished that thanks to the aforementioned 953 figure), rendering any age that any post-Time War Doctor gives to be of questionable accuracy. So while Twelve may claim to be over 2,000 years old, all that we can say with certainty is that he is very, very old.
According to Steven Moffat the Doctor does not, and cannot, know how old he is.
"The thing I keep banging on about is that he doesn't know what age he is. He's lying," said Moffat in 2010, "how could he know, unless he's marking it on a wall? He could be 8,000 years old, he could be a million. He has no clue. The calendar will give him no clues."
Thus the Doctor may not in fact be a thousand years older than before. He may just be saying that. It might just be the number the new doctor prefers to throw around.
He spent centuries (probably a thousand years in fact) in his last incarnation. The 11th Doctor was supposedly the longest lived incarnation, and it was the 13th, he aged until he became over 2000 years old. Though, I've roughly worked it out, and he is way off! He's more like over 4000 years old! Far older than he says he is. Think how long he spent in his 7th (he visibly aged) and 8th incarnations (listen to his Big Finish stories, and you'll see), and then how long he spent in his Warrior incarnation. In the Day of the Doctor, the War Doctor claims to be 800 years old, then afterwards, he regenerates into the 9th Doctor. By the time we see the 9th Doctor, he says he's 900 years old, so he's spent about a century in this body before meeting Rose. However, I have a theory: the reason he says he's 900 years old, is because he gradually lost track, and he spent 800 years fighting in the Time War, and just started counting again at that point.
David Tennant wa sapproximately 900 years old and when he regenerates into Matt Smith he lives for another thousand years. Shown when he goes to trenzalor aka the town of christmas. He lives and protects the people there for a thousand year therefore when regenerating into Peter Capoldi he is two thousand years old.
