With a malicious grin that implies I know something you don’t.

It was this celestial splendor that suddenly made me realize how little time, how little life, I had left. My sense of the heavens’ beauty, of eternity, was inseparably mixed for me with a sense of transience — and death. ... I told my friends Kate and Allen, “I would like to see such a sky again when I am dying.” “We’ll wheel you outside,” they said.

Swiftly, painlessly, and old.

Surrounded by my great-great-grandchildren.

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.

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.

Did the Victorians fear death? As Death says in one of my own books, most men don't fear death, they fear those things – the knife, the shipwreck, the illness, the bomb – that proceed, by micro seconds if you're lucky and many years if you're not, the moment of death.

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.

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.