He has recently learned that he has "multiple metastases in the liver," the kind of cancer that "cannot be halted." He has a detached, yet touching, article on "how [he plans] to live out the months that remain to me." Here's a section on some of his choices, and the reasons behind them:
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. [...]