The chief side effect of this pain is numbness in the extremities, filling me with the not irrational fear that I shall lose the ability to write. Without that ability, I feel sure in advance, my “will to live” would be hugely attenuated. I often grandly say that writing is not just my living and my livelihood but my very life, and it’s true. Almost like the threatened loss of my voice, which is currently being alleviated by some temporary injections into my vocal folds, I feel my personality and identity dissolving as I contemplate dead hands and the loss of the transmission belts that connect me to writing and thinking.

Missing a few months of feeling awful, being dead, versus not missing those months of feeling awful. Dead, at least theoretically, is the less painful of the two options, assuming that dead equals not being at all. Whatever terror there is lies in the present fear of dying, not so much of death. The stoics tell me that I’ve been ‘dead’ before, prior to my birth, and that was no hardship, was it? Back to Beckett, I think.

It was fear of suffering before dying, and of, you know, lingering on, being in a hospital bed. And I hate hospitals, always have done. I think they're horrible places, even though I spent most of my life working in them. No, it's really - death itself holds no fears for me at all, as far as - I love the famous 18th century philosopher David Hume, who on his deathbed was asked, aren't you terribly worried about what will happen after death? And he said, no, I'm no more worried about not existing after death than I'm worried about not existing before I was born. And that is my view about death. I don't believe in an afterlife. But I know, as a doctor, that dying can be very unpleasant.

Yes. Of course. And since I don't believe in another world, in another life, that this is it. And when they die they are out of my life. They're gone forever. Blank. Blank. Blank. And I am not afraid of death. And I begin to - as maybe a good many elderly people do. Who knows? When I did "Bumble-ardy" I was so intensely aware of death. Eugene, my friend and my partner, was dying here in the house while I did "Bumble-ardy." And I did "Bumble-ardy" to save myself. I did not want to die with him. I wanted to live, as any human being does.

When my father was in his terminal year, I discussed death with him. I recall very clearly his relief that the cancer that was taking him was at least allowing him "all his marbles". Dementia in its varied forms is not like cancer. Dad saw the cancer in his pancreas as an invader. But Alzheimer's is me, unwinding, losing trust in myself, a butt of my own jokes and on bad days capable of playing hunt the slipper by myself and losing. You can't battle it, you can't be a plucky "survivor". It steals you from yourself. And I'm 60; that's supposed to be the new 40.

It occurred to me that at one point it was like I had two diseases – one was Alzheimer's and the other was knowing I had Alzheimer's. There were times when I thought I'd have been much happier not knowing, just accepting that I'd lost brain cells and one day they'd probably grow back or whatever. It is better to know, though, and better for it to be known, because it has got people talking, which I rather think was what I had in mind.

I remember what George said and vowed that rather than let Alzheimer's take me, I would take it. I would live my life as ever to the full and die, before the disease mounted its last attack, in my own home, in a chair on the lawn, with a brandy in my hand to wash down whatever modern version of the "Brompton cocktail" some helpful medic could supply. And with Thomas Tallis on my iPod, I would shake hands with Death.

Let us consider me as a test case. As I have said, I would like to die peacefully with Thomas Tallis on my iPod before the disease takes me over and I hope that will not be for quite some time to come, because if I knew that I could die at any time I wanted, then suddenly every day would be as precious as a million pounds. If I knew that I could die, I would live. My life, my death, my choice.

When Milton's Satan stood in the pit of hell and raged at heaven, he was merely a trifle miffed compared to how I felt on that day. I felt totally alone, with the world receding away from me in every direction, and you could have used my anger to weld steel. Only my family and the fact I had fans in the medical profession, who were able to give me useful advice, got me through that moment.