THIS IS A FAIRY TALE. People stand in the lightly falling snow. Something is shining, trembling, making a silvery sound. Eyes are shining. Voices sing. People laugh and weep, clasp one another's hands, embrace.

Something shines and trembles. They live happily ever after. The snow falls on the roofs and blows across the parks, the squares, the river.

This is history. Once upon a time, a good king lived in his palace in a kingdom far away. But an evil enchantment fell upon that land. The wheat withered in the ear, the leaves dropped from the trees of the forest and nothing thrived.

This is a stone. It's a paving stone of a square that slants downhill in front of an old, reddish, almost windowless fortress called the Roukh Palace. The square was paved nearly 300 years ago, so a lot of feet have walked on this stone, bare feet and shod, children's little pads, horses' iron shoes, soldiers' boots; and wheels have gone over and over it, cart wheels, carriage wheels, car tires, tank treads. Dogs' paws every now and then. There has been dogshit on it, there has been blood, both soon washed away by water sloshed from buckets or run from hoses or dropped from the clouds. You can't get blood from a stone, they say, nor can you give it to a stone; it takes no stain. Some of the pavement, down near that street that leads out of Roukh Square through the old Jewish quarter to the river, got dug up, once or twice, and piled into a barricade, and some of the stones even found themselves flying through the air, but not for long. They were soon put back in their place, or replaced by others. It made no difference to them. The man hit by the flying stone dropped down like a stone beside the stone that had killed him. The man shot through the brain fell down and his blood ran out on this stone, or another one maybe; it makes no difference to them. The soldiers washed his blood away with water sloshed from buckets, the buckets their horses drank from. The rain fell after a while. The snow fell. Bells rang the hours, the Christmases, the New Years. A tank stopped with its treads on this stone. You'd think that that would leave a mark, a huge heavy thing like a tank, but the stone shows nothing. Only all the feet bare and shod over the centuries have worn a quality into it, not a smoothness, exactly, but a kind of softness, like leather or like skin. Unstained, unmarked, indifferent, it does have that quality of having been worn for a long time by life. So it is a stone of power, and who sets foot on it may be transformed.

This is a story. She let herself in with her key and called, "Mama? It's me, Fana!"

And her mother, in the kitchen of the apartment, called, "I'm in here," and they met and hugged in the doorway of the kitchen.

"Come on, come on!"

"Come where?"

"It's Thursday, Mama!"

"Oh," said Bruna Fabbre, retreating toward the stove, making vague protective gestures at the saucepans, the dishcloths, the spoons.

"You said."

"But it's nearly four already--"

"We can be back by six-thirty."

"I have all the papers to read for the advancement tests."

"You have to come, Mama. You do. You'll see!"

A heart of stone might resist the shining eyes, the coaxing, the bossiness. "Come on` she said, and the mother came. But grumbling. "This is for you," she said on the stairs. On the bus, she said it again. "This is for you. Not me. "What makes you think that?"

Bruna did not reply for a while, looking out the bus window at the gray city lurching by, the dead November sky behind the roofs.

"Well, you see," she said, "before Kasi, my brother Kasimir, before he was killed, that was the time that would have been for me. But I was too young. Too stupid. And then they killed Kasi."

"By mistake."

"It wasn't a mistake. They were hunting for a man who'd been getting people out across the border, and they'd missed him. So it was to... ."

"To have something to report to the Central Office." Bruna nodded. "He was about the age you are now," she said. The bus stopped, people climbed on, crowding the aisle. "Since then, twenty-seven years, always since then, it's been too late. For me. First too stupid, then too late. This time is for you. I missed mine."

"You'll see," Stefana said. "There's enough time to go round."

This is history. Soldiers stand in a row before the reddish, almost windowless palace; their muskets are at the ready. Young men walk across the stones toward them, singing, "Beyond this darkness is the light, 0 Liberty, of thine eternal day!" The soldiers fire their guns. The young men live happily ever after.

This is biology.

"Where the hell is everybody?"

"It's Thursday," Stefan Fabbre said, adding, "Damn!" as the figures on the computer screen jumped and flickered. He was wearing his topcoat over sweater and scarf, since the biology laboratory was heated only by a space heater that shorted out the computer circuit if they were on at the same time.

"There are programs that could do this in two seconds," he said, jabbing morosely at the keyboard. Avelin came up and glanced at the screen. "What is it?"

"The RNA comparison count. I could do it faster on my fingers." Avelin, a bald, spruce, pale, dark-eyed man of 40, roamed the laboratory, looked restlessly through a folder of reports. "Can't run a university with this going on," he said. "I'd have thought you'd be down there." Fabbre entered a new set of figures and said, "Why?"

"You're an idealist."

"Am l?" Fabbre leaned back, rolled his head to get the cricks out. "I try hard not to be," he said.

"Realists are born, not made." The younger man sat down on a lab stool and stared at the scarred, stained counter. "It's coming apart," he said.

"You think so? Seriously?" Avelin nodded. "You heard that report from Prague." Fabbre nodded.

"Last week... this week... next year--yes. An earthquake. The stones come apart--it falls apart--there was a building, now there's not. History is made. So, I don't understand why you're here, not there."

"Seriously, you don't understand?" Avelin smiled and said, "Seriously."

"All right." Fabbre stood up and began walking up and down the long room as he spoke. He was a slight gray-haired man with youthfully intense, controlled movements. "Science or political activity, either/or: Choose. Right? Choice is responsibility, right? So I chose my responsibility responsibly. I chose science and abjured all action but the acts of science. The acts of a responsible science. Out there, they can change the rules; in here, they can't change the rules; when they try to, I resist. This is my resistance." He slapped the laboratory bench as he turned round. "I'm lecturing. I walk up and down like this when I lecture. So. Background of the choice. I'm from the northeast. Fifty-six, in the northeast, do you remember? My grandfather, my father-reprisals. So, in Sixty, I come here, to the university. Sixty-two, my best friend, my wife's brother. We were walking through a village market, talking, then he stopped, he stopped talking, they had shot him. A kind of mistake. Right? He was a musician. A realist. I felt that I owed it to him, that I owed it to them, you see, to live carefully, with responsibility, to do the best I could do. The best I could do was this," and he gestured around the laboratory. "I'm good at it. So I go on trying to be a realist. As far as possible, under the circumstances, which have less and less to do with reality. But they are only circumstances. Circumstances in which I do my work as carefully as I can."