So what does all this tell us about how long the Doctor has spent in his various bodies down the centuries? Well, as the Second Doctor was relatively new in his skin, we can assume that the majority of those initial 450 years were spent as the William Hartnell model. If we discount The Mind Evil’s comment about being a scientist for “several thousand” as either a) typical Third Doctor showboating or b) referring to the Time Lord equivalent of dog years, and assume that the Fourth Doctor is still fairly freshly-minted in The Brain of Morbius (which he must be, as Sarah has been with him the whole time), that means he ages around 300 years over the course of his second and third incarnations. Everyone with me so far? Good.
Somewhere between mid-to-late Tom Baker and early Colin Baker, he racks up another 200 years. Again, they can’t be on the Sixth Doctor’s watch, as Peri hasn’t aged a day, so either the Fourth Doctor spends a couple of centuries exploring the universe with fellow Time Lord Romana, or Peter Davison’s Fifth Doctor was knocking about for a fair while.
The Sixth Doctor has a lifespan of roughly 50 years, while the Seventh, Eighth and War Doctors appear to have a bit of a mayfly existence – possible even going backwards – despite much evidence to the contrary.
The Ninth Doctor’s time is as fleeting as his screen tenure, but what might distress millions of David Tennant fans is the fact he also appears to have aged in something approaching real time. Can the iconic Tenth Doctor really only have clocked up six years, at most? The evidence would suggest so.
Finally, there’s no doubt about who has the most staying power: Matt Smith’s Eleventh Doctor was at the helm of the TARDIS for at least 1,197 years – more than all his predecessors put together. No wonder when he regenerated he said, “I’ll always remember when the Doctor was me.”
So there you go. If you think you can shed any more light on the matter, please leave your comments below. In the meantime, perhaps it would be easier if we all agreed that the Doctor is no spring chicken, and leave it at that.