But I did not understand this at the time. I was, after all, only eleven. I had a much more practical -- and heartless -- question.

"Why do we keep this park at all?" I asked. "I mean, they're going to live forever. And all the time they're alive, they pose a danger of this counterinfection getting loose outside the fence. Why haven't they all been killed and their bodies nuked or something so that the counteragent is eliminated?"

Mother looked appalled at my ruthlessness, but Father only patted her arm and said, "Of course he thought of that, my love."

"But so young, to be so-"

"Practical?" prompted Father. "There was a long debate over exactly this issue, and it resurfaced from time to time, though not for decades now: The ones who argued for keeping the park talked about the necessity of studying our ancestors, and some people talked about the rights of these citizens who, after all, can't help their medical condition and have committed no crime, but it was all a smoke screen. The real reason we didn't destroy them all, as you suggested, was because we didn't have the heart."

"They were our children," said Mother, crying again.

"At first," said Father. "And later, when they weren't children anymore, we still couldn't kill them. Because they had become our ancient parents."

Now, though, I have come to think that while they were both right, the answer is even deeper. We didn't kill them, and we continue not to kill them, despite the reality of all those dangers, because they are not "they" at all. There, but for the fact that we happen to be the tiniest bit ill, go we.

I had troubling dreams for months afterward. I had mood swings, alternating between aggression and despair. At times, my parents wished they had just answered my questions about Elizio by taking me to the priest and getting me on the roster of altar boys.