she said. Yet she already knew the answer: the military. Not different from Earth’s sometimes-not-so-distant past at all; in every war, whether with guns or experimental craft or bioweapons, soldiers were fodder. Sometimes they knew what was happening, and why. Many times they didn’t.“They were desperate,” said Saad, as if reading her mind. “We’re all desperate, Elizabeth, just in different ways. So they did it.”“And?”“At first, it didn’t work. They had the same problem with rejection.”“But that’s what’s so strange about this whole thing,” she said, without really thinking it over first. “I don’t understand the violence of this rejection business. The brain’s relatively privileged, comparatively well isolated antigenically.”She was only aware when the silence grew that Saad was staring, as was Mara. It occurred to her, too late, that human brains were privileged. But here, their spleen and thymus are so large, probably hyperreactive to stimulus…She thought about trying to backtrack but then figured she’d put her boot in it.