Free Stork Naked by Piers Anthony

from its beak.
    “Normal time,” Pyra said.
    The stork slowed to regular motion, approaching the house. The door opened and Surprise stood there. There was a brief dialogue they couldn't hear, as the screen was soundless. Then the stork turned, spread its wings, and flew away, bearing its bundle.
    “That was it,” Surprise said, tears in her eyes. It seemed like an age since she lost her baby, but had been only a few hours. “But how can this—this mask—make such accurate pictures?”
    “This is only part of its functioning,” Pyra said. “It selects specified pictures, masking irrelevant ones. In this case I confined it to this reality.” The image of the stork returned, this time unmoving, like a painted picture.
    “This reality,” Surprise echoed, remembering the discussion she had had with Che.
    “Here is the same scene without masking.” The screen became blank again.
    “But it shows nothing!”
    “No, it shows everything. All the realities. Now I shall mask out a number.” Pyra paused, then spoke to the frame. “Mask all without storks.”
    The screen flickered, but remained opaque.
    “Mask all without balks.”
    The screen became filled with tiny images of still storks. Surprise gazed at them, amazed anew.
    “Mask all female storks.”
    Now half the number of pictures appeared, each twice the prior size.
    “We can reduce it to a single picture, in a single reality,” Pyra said. “But it will be the wrong picture, or the wrong reality, if the masking is not proper. Do you care to try it?”
    Surprise knew better, but gambled. “Yes.”
    Pyra put the frame in her hands. “Try zeroing in on the same scene,” she suggested.
    The picture had reverted to blank. Now Surprise understood that this was actually a display of so many tiny pictures that each was the size of a dot. She had to reduce their number by masking out the irrelevant ones.
    “Mask all storks,” she said.
    Nothing happened.
    “What you have now is all the scenes that don't contain storks,” Pyra explained. “An infinite number.”
    Oh. “Mask all without storks,” Surprise said.
    There seemed to be no change. There were too many with storks. “Mask all where the stork doesn't balk.”
    Now she got the myriad tiny pictures. But it wasn't the same; the house was gone. “What happened?”
    “You allowed the scene to drift. You have to keep it steady with your hands, as it is responsive to motion of the frame.”
    Surprise realized that even copying what she had just seen, she was fouling up. How would she have done entirely on her own? “You're right; I'm not good at this,” she said, handing the Mask back.
    “It requires years of practice,” Pyra said, laying it back down on the table. “I still don't have it perfectly.”
    “I don't have years! I have to do this in hours!” Surprise realized she was verging on hysteria, a human failing.
    “I doubt I would do any better,” Che said. “Pyra, what is your purpose?”
    “Take me with you. I will operate the Mask.” She picked up the frame and folded it so that it became a mere stick, and tucked it into her belt.
    Surprise quailed. They had barely avoided having Azalea accompany them, and here was another. “The Good Magician said that only two adults could go on this mission. The rest had to be children, animals, or crossbreeds.”
    “You have only one adult human,” Pyra said. “The centaur is a crossbreed.”
    “We're an established species!” Che protested.
    “An established crossbreed species. But I suppose I could use the Mask to seek the man with the Numbers Validity talent.”
    “I don't understand,” Surprise said, nettled.
    “He works with numbers. He can make a limit of n work for n+1. If we consult him I'm sure he will validate the mission for three adults.”
    Surprise was blank, but Che, being a centaur, understood about n and n+1. It seemed it was indeed possible to make numbers perform. They would have to find some other way to dissuade the