He refilled his teacup, allowing Ascar to interrupt with: “But there is time.”
Shiu nodded patiently. “Localised, accidental phenomena without overall significance. Processes of time can begin over small areas, usually associated with a planet, though not always. They consist of flows or waves of energy travelling from one point to another: small, travelling waves of ‘now’. Philosophically it’s explained thus: the universe issued from the Supreme as an interplay between the forces of yin and yang to form a perfect, dealocked harmonic balance. Occasionally these forces get a little out of balance with one another here and there, and this causes time energy to flow until the balance is redressed. As such a wave proceeds it organises matter into living forms in the process we know as evolution.”
“So time is a biological phenomenon, not a universal one?”
“Rather, biology is a consequence of time. Biological systems aren’t the only phenomena it can produce. There are – many variations. But life and consciousness can arise in the moving present moment and be carried along with it.
“You can see now why time travel is comparatively easy,” Shiu went on. “We merely have to detach a fragment of the travelling ‘now-wave’ and move it about the real static world of non-time. It comes away quite easily, because it’s local energy, not part of a cosmic schema.”
“Yes, and we’ve found that you need a living presence to make a time machine work,” Ascar agreed. “That would follow, too.”
“Only because your machinery is primitive. In Retort City we can dispatch inanimate objects through time as well.”
“Yes… I see.…”
Ascar strained to grasp in entirety the vision Shiu Kung-Chien was presenting to him. “So let’s put this together,” he said with difficulty. “The universe consists of a static four-dimensional matrix –”
“Not four-dimensional,” Shiu corrected. “Your whole theories about dimensions are erroneous: there are no dimensions. But if you want to use them as a descriptive tool, that’s all right. In that case a six-dimensional matrix would suffice to describe all the possible directions that exist. Time-waves, when they arise, can take any one of these directions – from our point of view, forward, backward, sideways, up, down, inside-out – directions impossible to envisage. But the wave-front always abstracts, as it proceeds, a three-dimensional environment to anyone who is inside it. And it always creates, for an observer trapped in it, a past and a future.”
“And the Regression Problem,” Ascar reminded him. “What happens to that?”
“There is no Regression Problem. The problem only arises when time is thought of as an absolute factor in the universe. But it’s an incidental factor only, a triviality. The universe as a whole doesn’t notice, is indifferent to, time, as well as to all the phenomena such as living creatures which it produces. Therefore there’s no contradiction about before and after, past and future, or the moving moment. There is, as far as the universe is concerned, no change; non-time swallows it all up without a whisper.”
Considerately, Shiu gave Ascar time to mull this over. The Earth physicist placed his chin on his hand, gazing at the floor.
“And so this is what’s happened to Earth?” he said finally. “Another time-system has taken root on it, creating another process of evolution… but travelling in the reverse direction to ours. And they’re going to collide.”
“Correct,” affirmed Shiu in a neutral voice.
“I still have difficulty with this. With the idea of time travelling in reverse, but producing the same effects as our own time. I’ve been used to regarding physical laws, such as chemical reactions and the laws of thermodynamics, as working only one way. The laws of entropy, for instance… that would seem to give time a definite direction irrespective.…”
“That’s because you’re accustomed to looking upon time as an absolute function. To take the law of entropy – the law that disorder increases with time – the time-wave itself produces this effect. There are two contrasting modes in every time-wave: first, the tendency toward increasing disorder, and second, the tendency toward increasing integration, which results in biological systems. These tendencies are due to the yin and yang forces which are present in the time-wave, but battling against one another instead of harmonising. Yin brings the tendency toward integration, and yang brings the tendency toward disorder. When they cease to war with one another, time dies away.”
“But that’s not how it’s going to be on Earth?”
“No. Your civilisation is most unfortunate, as also is the civilisation which is going to collide with yours. It will be a violent, catastrophic conflict between irreconcilable powers – the weirdest, most fantastic event, perhaps, that can happen in this universe.”
“What will happen?”
“Almost certainly the end result will be that time will cease. The two wave-fronts will cancel one another out in a sort of time explosion.”
“What I really meant was,” Ascar said, avoiding Shiu’s eye, “what will it be like for the people on location – caught on the spot when the wave-fronts came within range of one another?”
“You want to know what it will be like?” Shiu said. “To a certain extent, I can show you.”
He rose and walked toward the other side of the laboratory, making for a transparent sphere about eight feet in diameter. “Retort City once suffered a similar incident.”
Ascar sprang to his feet and joined him. “And you survived?” he exclaimed.
“It wasn’t quite as disastrous as it will be with you,” Shiu told him mildly. “For one thing, the angle of approach was small – the entity we encountered was moving obliquely to us through time, not in head-on collision as will be the case with you. For another, we gained an advantage from our situation here in interstellar space. We were forewarned and were able to move ourselves, so that there was no actual physical contact. Nevertheless the wave-fronts did interfere with one another, and the effects were extremely unpleasant. It’s the closest we’ve come to annihilation.”
He halted before the transparent sphere. “At the time some all-sense tapes were made of the event. Do you have all-sense recording on Earth?”
Dumbly Ascar shook his head.
“As its name implies, it gives a record covering all the senses – all the external senses, and besides that the internal senses as well, such as body feeling, and so on. Where the senses are, the mind is; therefore you won’t be able to distinguish the experience from the real thing.”
He turned to his guest. “I’ll play you one of these sense-tapes if you like. I warn you it will be somewhat disturbing.”
“Yes, yes,” Ascar said eagerly. “I want to know what happens.”
Shiu nodded, his expression withdrawn and unreadable, and directed Ascar to enter the sphere by a narrow hatchway which closed up behind him. Once Ascar could no longer see him he smiled faintly to himself. He was unexpectedly pleased with the Terran visitor; despite his barbarian origin he was proving to be an apt pupil.
From within, the walls of the sphere were opaque. There was a dim light, by which Ascar saw a chair fixed to the floor. He sat on it, and as he did so the light went out, leaving him in pitch-darkness.
For a few moments nothing happened. Then light sprang into being again. But he was no longer in the glass sphere. He was sitting in a similar chair in a typically light, airy room in Retort City. The air carried a mingle of faint scents, and from somewhere came strains of the jangly, hesitating music that was popular here.