"Excuse me, but why did we stop?" he said.

"Philosophers have right of way," said the soldier.

"What's a philosopher?" said Brutha.

"Someone who's bright enough to find a job with no heavy lifting," said a voice in his head.

"An infidel seeking the just fate he shall surely receive,' said Vorbis. "An inventor of fallacies. This cursed city attracts them like a dung heap attracts flies."

"Actually, it's the climate," said the voice of the tortoise. "Think about it. If you're inclined to leap out of your bath and run down the street every time you think you've got a bright idea, you don't want to do it somewhere cold. If you do do it somewhere cold, you die out. That's natural selection, that is. Ephebe's known for its philosophers. It's better than street theater."

"What, a lot of old men running around the streets with no clothes on?" said Brutha, under his breath, as they were marched onward.

"More or less. If you spend your whole time thinking about the universe, you tend to forget the less important bits of it. Like your pants. And ninety-nine out of a hundred ideas they come up with are totally useless."

"Why doesn't anyone lock them away safely, then? They don't sound much use to me," said Brutha.

"Because the hundredth idea," said Om, "is generally a humdinger."

"What?"

"Look up at the highest tower on the rock."

Brutha looked up. At the top of the tower, secured by metal bands, was a big disc that glittered in the morning light.

"What is it?" he whispered.

"The reason why Omnia hasn't got much of a fleet any more," said Om. "That's why it's always worth having a few philosophers around the place. One minute it's all Is Truth Beauty and Is Beauty Truth, and Does a Falling Tree in the Forest Make a Sound if There's No one There to Hear It, and then just when you think they're going to start dribbling one of 'em says, Incidentally, putting a thirty-foot parabolic reflector on a high place to shoot the rays of the sun at an enemy's ships would be a very interesting demonstration of optical principles," he added. "Always coming up with amazing new ideas, the philosophers. The one before that was some intricate device that demonstrated the principles of leverage by incidentally hurling balls of burning sulphur two miles. Then before that, I think, there was some kind of an underwater thing that shot sharpened logs into the bottom of ships."

Brutha stared at the disc again. He hadn't understood more than one-third of the words in the last statement.

"Well," he said, "does it?"

"Does what?"

"Make a sound. If it falls down when no one's there to hear it."

"Who cares?"

The party had reached a gateway in the wall that ran around the top of the rock in much the same way that a headband encircles a head. The Ephebian captain stopped, and turned.

"The . . . visitors . . . must be blindfolded," he said.

"That is outrageous!" said Vorbis. "We are here on a mission of diplomacy!"

"That is not my business," said the captain. "My business is to say: If you go through this gate you go blindfolded. You don't have to be blindfolded. You can stay outside. But if you want to go through, you got to wear a blindfold. This is one of them life choices."

One of the subdeacons whispered in Vorbis's ear. He held a brief sotto voce conversation with the leader of the Omnian guard.

"Very well," he said, "under protest."

The blindfold was quite soft, and totally opaque. But as Brutha was led . . .

. . . ten paces along a passage, and then left five paces, then diagonally forward and left threeand-a-half paces, and right one hundred and three paces, down three steps, and turned around seventeen-and-one-quarter times, and forward nine paces, and left one pace, and forward nineteen paces, and pause three seconds, and right two paces, and back two paces, and left two paces, and turned threeand-a-half times, and wait one second, and up three steps, and right twenty paces, and turned around five-and-a-quarter times, and left fifteen paces, and forward seven paces, and right eighteen paces, and up seven steps, and diagonally forward, and pause two seconds, right four paces, and down a slope that went down a meter every ten paces for thirty paces, and then turned around seven-and-a-half times, and forward six paces . . .

. . . he wondered what good it was supposed to do.

The blindfold was removed in an open courtyard, made of some white stone that turned the sunlight into a glare. Brutha blinked.

Bowmen lined the yard. Their arrows were pointing downwards, but their manner suggested that pointing horizontally could happen any minute.

Another bald man was waiting for them. Ephebe seemed to have an unlimited supply of skinny bald men wearing sheets. This one smiled, with his mouth alone.

No one likes us much, Brutha thought.

"I trust you will excuse this minor inconvenience," said the skinny man. "My name is Aristocrates. I am secretary to the Tyrant. Please ask your men to put down their weapons."

Vorbis drew himself up to his full height. He was a head taller than the Ephebian. Pale though his complexion normally was, it had gone paler.

"We are entitled to retain our arms!" he said. "We are an emissary to a foreign land!"

"But not a barbarian one," said Aristocrates mildly. "Weapons will not be required here."

"Barbarian?" said Vorbis. "You burned our ships!"

Aristocrates held up a hand.

"This is a discussion for later," he said. "My pleasant task now is to show you to your quarters. I am sure you would like to rest a little after your journey. You are, of course, at liberty to wander anywhere you wish in the palace. And if there is anywhere where we do not wish you to wander, the guards will be sure to inform you with speed and tact."

"And we can leave the palace?" said Vorbis coldly.

Aristocrates shrugged.

"We do not guard the gateway except in times of war," he said. "If you can remember the way, you are free to use it. But vague perambulations in the labyrinth are unwise, I must warn you. Our ancestors were sadly very suspicious and put in many traps out of distrust; we keep them well-­greased and primed, of course, merely out of a respect for tradition. And now, if you would care to follow me . . ."

The Omnians kept together as they followed Aristocrates through the palace. There were fountains. There were gardens. Here and there groups of people sat around doing nothing very much except talking. The Ephebians seemed to have only a shaky grasp of the concepts of "inside" and "outside"-except for the palace's encircling labyrinth, which was very clear on the subject.

"Danger attends us at every turn," said Vorbis quietly. "Any man who breaks rank or fraternizes in any way will explain his conduct to the inquisitors. At length."

Brutha looked at a woman filling a jug from a well. It did not look like a very military act.

He was feeling that strange double feeling again. On the surface there were the thoughts of Brutha, which were exactly the thoughts that the Citadel would have approved of. This was a nest of infidels and unbelievers, its very mundanity a subtle cloak for the traps of wrong thinking and heresy. It might be bright with sunlight, but in reality it was a place of shadows.