My name is Terry Pratchett, author of a series of inexplicably successful fantasy books and I have had Alzheimer's now for the past two years plus, in which time I managed to write a couple of bestsellers. I have a rare variant. I don't understand very much about it, but apparently if you are going to have Alzheimer's it's a good one to have. So, a stroke of luck there then! Interestingly enough, when I was diagnosed last December by those nice people at Addenbrooke's, I started a very different journey through dementia. This one had much better scenery, interesting...