So many times I’ve wondered what might have happened to me if I had lost my legs, or even just my right one, where my first melanoma appeared two or three years later. If I’d just been a second slower stepping away from the car, I might not be dying now. I’d be legless, of course, but still in good health. Of these fateful forks in the road are our lives made up. We are all just a millimetre away from death, all of the time, if only we knew it.

Not being able to have a baby for two and a half years. Lots of people say it made me a better person; I think it made me worse. You go to a very dark place with your friends because they are having kids, and you want to be happy for them but you’re not.

Trusting some men.

I am a living self-help book – I’ve managed to train myself to never regret anything.

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.

I cannot pretend I am without fear. But my predominant feeling is one of gratitude. I have loved and been loved; I have been given much and I have given something in return; I have read and traveled and thought and written. I have had an intercourse with the world, the special intercourse of writers and readers. Above all, I have been a sentient being, a thinking animal, on this beautiful planet, and that in itself has been an enormous privilege and adventure.

My generation is on the way out, and each death I have felt as an abruption, a tearing away of part of myself. There will be no one like us when we are gone, but then there is no one like anyone else, ever. When people die, they cannot be replaced. They leave holes that cannot be filled, for it is the fate — the genetic and neural fate — of every human being to be a unique individual, to find his own path, to live his own life, to die his own death.

The first biography I read — I think the first scientific biography — was Madame Curie . And my mother, who was a surgeon, worked at the Marie Curie Hospital. She’d met Marie Curie, who was one of her great heroines. And reading the book, I think, was the first portrait of a scientist and the romance of a scientific life.

I feel a sudden clear focus and perspective. There is no time for anything inessential. I must focus on myself, my work and my friends. I shall no longer look at “NewsHour” every night. I shall no longer pay any attention to politics or arguments about global warming. This is not indifference but detachment — I still care deeply about the Middle East, about global warming, about growing inequality, but these are no longer my business; they belong to the future. I rejoice when I meet gifted young people — even the one who biopsied and diagnosed my metastases. I feel the future is in good hands.

And now, weak, short of breath, my once-firm muscles melted away by cancer, I find my thoughts, increasingly, not on the supernatural or spiritual, but on what is meant by living a good and worthwhile life — achieving a sense of peace within oneself. I find my thoughts drifting to the Sabbath, the day of rest, the seventh day of the week, and perhaps the seventh day of one’s life as well, when one can feel that one’s work is done, and one may, in good conscience, rest.