Yet if you don't understand the physiology of a biological system or process-like female sexual arousal-you can't possibly come up with a way to fix it when things go wrong. No one would have come up with a treatment for diabetes if physiologists hadn't figured out how metabolism, blood sugar, and insulin work.

The simplest strategy for bouts of noxious flatus is to not care. Or perhaps to take advantage of a gastroenterologist I know: get a dog. (To blame.)

Sharing a room with a cadaver is only mildly different from being in a room alone. They are the same sort of company as people across from you on subways or in airport lounges, there but not there. Your eyes keep going back to them, for lack of anything more interesting to look at, and then you feel bad for staring.

It is astounding to me, and achingly sad, that with eighty thousand people on the waiting list for donated hearts and livers and kidneys, with sixteen a day dying there on that list, that more then half of the people in the position H's family was in will say no, will choose to burn those organs or let them rot. We abide the surgeon's scalpel to save our own lives, out loved ones' lives, but not to save a stranger's life. H has no heart, but heartless is the last thing you'd call her.

All good research-whether for science or for a book-is a form of obsession.

There are people who would love to spend their last ten years, or five years, or whatever it is, on the surface of Mars.

The point is that no matter what you choose to do with your body when you die, it won't, ultimately, be very appealing. If you are inclined to donate yourself to science, you should not let images of dissection or dismemberment put you off. They are no more or less gruesome, in my opinion, than ordinary decay or the sewing shut of your jaws via your nostrils for a funeral viewing.