The two alternatives left then to us were either to emigrate to the United States, or to pursue some activity that needed neither support nor connection with the outside Aryan world where we lived. My family chose this second alternative. I then decided to build a small research unit at home and installed it in my bedroom. My inspiration was a 1934 article by Viktor Hamburger reporting on the effects of limb extirpation in chick embryos. My project had barely started when Giuseppe Levi, who had escaped from Belgium invaded by Nazis, returned to Turin and joined me, thus becoming, to my great pride, my first and only assistant.

I went through some really terrible times. I don’t know whether I should really even mention it, but you mentioned that I had to go to prison and all that stuff. I was in a state where they had me in a straitjacket at one time. Can you understand what it would feel like to be in a straitjacket? I know. I couldn’t either, but I was, and it was brought about by sort of a drug psychosis in prison. I mean I just went completely… But it was tough, it was tough. I mean at that time they put you in — there’s a place in New York they used to call the Tombs. You’ve probably heard of it. I mean it was like a living tomb, with all the people. So I was there, and the withdrawal — physical symptoms, which were unbelievable.

And in the end they robbed us, but they did let us go. But I think that that was a very useful lesson early in my journalism career, that things can go very badly wrong. At one moment you can be going down a road and things are perfect, and the next moment you’ve got some drunk soldiers who just may kill you. That fear that I felt when they were holding us for maybe 45 minutes or so in the jungle, that has never entirely left me.

Look, life is pretty dreadful most of the time. Even in the country that's so pretty with the flowers and leaves and sunshine. And I was abandoned when he died! I'm alone. I feel like an old bubba. And I'm not kind all of the time, I'm not nice all the time.

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.

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.

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.

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.

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.