When you write a character, it has to be genuine. We all know that, right? I produce pages of details I never use, because the reader doesn't need to know them all - but I do. They help me work out how the character will react in a given situation. I can't really have a bloke who's homophobic then turn out to be bisexual, can I?
Motivation matters. A person's history, his family's background, a thousand other things; they all go into making that person who he or she is. That controls how the character behaves. And that's why I'm having trouble with the idea of Doctor Who as a woman.
Let me say first that I like diversity. The BBC (who makes Dr Who) is in trouble for having too few ethnic minority stars, and above all for paying its male staff much, much more than their female counterparts. It deserves that trouble, too. It pays lots of men over £1 million a year, but no woman earns half that. It's a disgrace.
But turning the Doctor into a woman doesn't feel like diversity. It feels like ticking a box. The current companion is Bill, who ticks three boxes - ethnic minority, female, gay. The BBC is straining so hard to be right-on politically correct that it risks losing sight of what the character actually is.
The Doctor was conceived as an antidote to all the comic-book superheroes of the 1950's and '60's. Give them a spider bite or a radiation accident and they started to defy evil by hitting it a lot. By contrast, the Doctor never used violence. He used cleverness instead. He was intended to show young boys that cleverness was just as cool as flying about in a red cape and punching the bad guy on the nose.
But girls know that already, you don't have to teach them. Women know how to talk better than men, how to compromise, because they don't have all this testosterone and ego thrashing about inside them. OK, these are generalisations, but they're largely true. So where does this leave the Doctor? A woman who prefers to talk and use her wits isn't anything out of the ordinary.
As for the show, it's gained a transgender Doctor, but lost the multi-box ticking Bill. That needs to be addressed, gosh yes, I'm horribly afraid that the next season or two will give us a gay Cyberman, a female Dalek, maybe a Weeping Angel from a persecuted minority of the species. It's all very modern, but you know, modern changes. Twenty years from now the Doctor is likely to look as dated as the original Star Trek - the Sixties in space, more or less.
Making the Doctor female is just tokenism. If the BBC wants to do diversity properly, instead of just filling quotas, here's how.
(Roly is my favourite)
Night night, Squirrels.