Some of those late nights.

As I look back on those days, it’s just like a dream. The only thing that bothered me was that we waited so long to make this protest and to let it be known wherever we go that all of us should be free and equal and have all opportunities that others should have.

I would have articulated aloud the comments I too often suppressed out of deference to arrogant, condescending, sexist bores.

I would have been OK with feeling shy. In my teenage years, I thought being an actor meant that you had to be a little more performative.

And I spent four years at a boarding school in the country, probably a rather abusive boarding school, and seeing very little of my parents, and that was a very bad time for me. A bad and almost a mad time. ... I think that some sort of trust, and ability for closeness, may have been compromised. And I think I’ve perhaps, to some extent, sort of kept a distance since that time, although this is not a distance I feel with my patients or my students.

On the contrary, I feel intensely alive, and I want and hope in the time that remains to deepen my friendships, to say farewell to those I love, to write more, to travel if I have the strength, to achieve new levels of understanding and insight. This will involve audacity, clarity and plain speaking; trying to straighten my accounts with the world. But there will be time, too, for some fun (and even some silliness, as well).

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.

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.

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.

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.