Finally he asked, “Are there other islands?” Not merely other histories, sharing the same underlying basis, but other realities entirely.
“I suspect so,” Helen replied. “People have mapped some possibilities. I don’t know how that could ever be confirmed, though.”
Robert shook his head, sated. “I won’t even think about that. I need to come down to Earth for a while.”
He stretched his arms and leaned back, still grinning.
Helen said, “Where’s Luke today? He usually shows up by now, to drag you out into the sunshine.”
The question wiped the smile from Robert’s face. “Apparently I make poor company. Being insufficiently fanatical about darts and football.”
“He’s left you?” Helen reached over and squeezed his hand sympathetically. A little mockingly, too.
Robert was annoyed; she never said anything, but he always felt that she was judging him. “You think I should grow up, don’t you? Find someone more like myself. Some kind ofsoulmate.” He’d meant the word to sound sardonic, but it emerged rather differently.
“It’s your life,” she said.
A year before, that would have been a laughable claim, but it was almost the truth now. There was a de facto moratorium on prosecutions, while the recently acquired genetic and neurological evidence was being assessed by a parliamentary subcommittee. Robert had helped plant the seeds of the campaign, but he’d played no real part in it; other people had taken up the cause. In a matter of months, it was possible that Quint’s cage would be smashed, at least for everyone in Britain.
The prospect filled him with a kind of vertigo. He might have broken the laws at every opportunity, but they had still molded him. The cage might not have left him crippled, but he’d be lying to himself if he denied that he’d been stunted.
He said, “Is that what happened, in your past? I ended up in some…lifelong partnership?” As he spoke the words, his mouth went dry, and he was suddenly afraid that the answer would be yes.With Chris.
The life he’d missed out on was a life of happiness with Chris.
“No.”
“Then…what?” he pleaded. “What did I do? How did I live?” He caught himself, suddenly self-conscious, but added, “You can’t blame me for being curious.”
Helen said gently, “You don’t want to know what you can’t change. All of that is part of your own causal past now, as much as it is of mine.”
“If it’s part of my own history,” Robert countered, “don’t I deserve to know it? This man wasn’t me, but he brought you to me.”
Helen considered this. “You accept that he was someone else? Not someone whose actions you’re responsible for?”
“Of course.”
She said, “There was a trial, in 1952. For ‘Gross Indecency contrary to Section 11 of the Criminal Amendment Act of 1885.’ He wasn’t imprisoned, but the court ordered hormone treatments.”
“Hormone treatments?”Robert laughed. “What-testosterone, to make him more of a man?”
“No, estrogen. Which in men reduces the sex drive. There are side-effects, of course. Gynecomorphism, among other things.”
Robert felt physically sick.They’d chemically castrated him, with drugs that had made him sprout breasts . Of all the bizarre abuse to which he’d been subjected, nothing had been as horrifying as that.
Helen continued, “The treatment lasted six months, and the effects were all temporary. But two years later, he took his own life. It was never clear exactly why.”
Robert absorbed this in silence. He didn’t want to know anything more.
After a while, he said, “How do you bear it? Knowing that in some branch or other, every possible form of humiliation is being inflicted on someone?”
Helen said, “I don’tbear it. I change it. That’s why I’m here.”
Robert bowed his head. “I know. And I’m grateful that our histories collided. But…how many historiesdon’t?” He struggled to find an example, though it was almost too painful to contemplate; since their first conversation, it was a topic he’d deliberately pushed to the back of his mind. “There’s not just an unchangeable Auschwitz in each of our pasts, there are an astronomical number of others-along with an astronomical number of things that are even worse.”
Helen said bluntly, “That’s not true.”
“What?” Robert looked up at her, startled.
She walked to the blackboard and erased it. “Auschwitz has happened, for both of us, and no one I’m aware of has ever prevented it-but that doesn’t mean thatnobody stops it, anywhere.” She began sketching a network of fine lines on the blackboard. “You and I are having this conversation in countless microhistories-sequences of events where various different things happen with subatomic particles throughout the universe-but that’s irrelevant to us, we can’t tell those strands apart, so we might as well treat them all as one history.” She pressed the chalk down hard to make a thick streak that covered everything she’d drawn. “The quantum decoherence people call this ‘coarse graining.’ Summing over all these indistinguishable details is what gives rise to classical physics in the first place.
“Now, ‘the two of us’ would have first met in many perceivably different coarse-grained histories-and furthermore, you’ve since diverged by making different choices, and experiencing different external possibilities, after those events.” She sketched two intersecting ribbons of coarse-grained histories, and then showed each history diverging further.
“World War II and the Holocaust certainly happened in both ofour pasts-but that’s no proof that the total is so vast that it might as well be infinite. Remember, what stops us successfully intervening is the fact that we’re reaching back to a point where some of the parallel interventions start to bite their own tail. So when we fail, it can’t be counted twice: it’s just confirming what we already know.”
Robert protested, “But what about all the versions of thirties Europe that don’t happen to lie in either your past or mine? Just because we have no direct evidence for a Holocaust in those branches, that hardly makes it unlikely.”
Helen said, “Not unlikelyper se, without intervention. But not fixed in stone either. We’ll keep trying, refining the technology, until we can reach branches where there’s no overlap with our own past in the thirties. And there must be other, separate ribbons of intervention that happen in histories we can never even know about.”
Robert was elated. He’d imagined himself clinging to a rock of improbable good fortune in an infinite sea of suffering-struggling to pretend, for the sake of his own sanity, that the rock was all there was. But what lay around him was not inevitably worse; it was merely unknown. In time, he might even play a part in ensuring that every last tragedy wasnot repeated across billions of worlds.
He reexamined the diagram. “Hang on. Intervention doesn’t end divergence, though, does it? You reachedus, a year ago, but in at least some of the histories spreading out from that moment, won’t we still have suffered all kinds of disasters, and reacted in all kinds of self-defeating ways?”
“Yes,” Helen conceded, “but fewer than you might think. If you merely listed every sequence of events that superficially appeared to have a nonzero probability, you’d end up with a staggering catalog of absurdist tragedies. But when you calculate everything more carefully, and take account of Planck-scale effects, it turns out to be nowhere near as bad. There areno coarse-grained histories where boulders assemble themselves out of dust and rain from the sky, or everyone in London or Madras goes mad and slaughters their children. Most macroscopic systems end up being quite robust-people included. Across histories, the range of natural disasters, human stupidity, and sheer bad luck isn’t overwhelmingly greater than the range you’re aware of from this history alone.”
Robert laughed. “And that’s not bad enough?”
“Oh, it is. But that’s the best thing about the form I’ve taken.”
“I’m sorry?”
Helen tipped her head and regarded him with an expression of disappointment. “You know, you’re still not as quick on your feet as I’d expected.”
Robert’s face burned, but then he realized what he’d missed, and his resentment vanished.
“You don’t diverge?Your hardware is designed to end the process? Your environment, your surroundings, will
