tochange history that was already past. The theory said that if we couldturn the social patterns and technological trends just slightly awayfrom what they were, we could alter the entire makeup of society inour own time. And the Equation was the tool, the final check on anychange. The Equation which evaluates the sum of social, psychologicaland energy factors in any situation, any city or nation or humansociety. The Equation has been proven, checked time and time again,but the theory didn't fit it. The theory was wrong."
Roger Strang sat up, suddenly alert. "That boy," he said, his voicesharp. "You nearly made a sieve of him, trying to shoot him. Whydidn't he die?"
"Because he was on a high-order variable. Picture it this way: Fromany point in time, the possible future occurrences could be seen asvectors, an infinite number of possible vectors. Every activity thatmakes an alteration, or has any broad effect on the future is ahigh-order variable, but many activities have no grave implicationsfor future time, and could be considered unimportant, or low-ordervariables. If a man turns a corner and sees something that stimulateshim into writing a world-shaking manifesto, the high-order variablewould have started when he decided to turn the corner instead of goingthe other way. But if he took one way home instead of another, andnothing of importance occurred as a result of the decision, alow-order variable would be set up.
"We found that the theory of alterations held quite well, forlow-order variables. Wherever we appeared, whatever we did, we set upa definite friction in the normal time-stream, a distortion, likepulling a taut rubber band out. And we could produce changes--onlow-order variables. But the elasticity of the distortion was so greatas to warp the change back into the time-stream without causing anylasting alteration. When it came to high-order changes, _we simplycouldn't make any_. We tried putting wrong data into the machines thatwere calculating specifications for the Barrier, and the false datawent in, but the answers that came out were answers that _should_ haveappeared with the _right_ data. We tried to commit a murder, to killDavid Strang, and try as we would we couldn't do it. Because it wouldhave altered a high-order variable, and they simply _wouldn't bealtered_!"
"But you, Morrel," Roger exclaimed. "How about you? You were top manin the Barrier Base Security office. You must have made animpression."
Morrel smiled tiredly. "I really thought I had, time after time. Iwould start off a series of circumstances that should have had a gravealterative effect, and it would look for awhile as if a long-rangechange was going to be affected--and then it would straighten itselfout again, with no important change occurring. It was maddening. Weworked for five years trying to make even a small alteration--andbrought back our data--" He pointed to the papers on the floor. "Thereare the calculations, applied on the Equation. Meaningless. Weaccomplished nothing. And the Dictator is still there."
Drengo slumped in his chair. "And he's started the war. The realattack. This bombardment outside is nothing. There are fifteensquadrons of space-destroyers already unloading atomic bombs on thesurface of Mars, and that's the end, for us. Farrel Strang has starteda war he can never finish--"
Roger Strang turned sharply to Drengo. "This Dictator," he said."Where is he? Why can't he be reached now, and destroyed?"
"The Barrier. He can't be touched in the Palace. He has all hisoffices there, all his controls, and he won't let anyone in since theattempted assassination three months ago. He's safe there, and wecan't touch him."
Roger scowled at the control panel on the wall. "How does thistime-portal work?" he asked. "You say it can take us back--_why notforward?_"
"No good. The nature of Time itself makes that impossible. At thepresent instant of Time, everything that has happened has happened.The three-dimensional world in which we live has passed through thefourth temporal dimension, and nothing can alter it. But at thisinstant there are an infinite number of things that could happen next.The future is an infinite series of variables, and there's noconceivable way to predict which variable will actually be true."
Roger Strang sat up straight, staring at Drengo. "Will that portalwork both ways?" he asked tensely.
Drengo stared at him blankly. "You mean, can it be reverse-wired? Isuppose so. But--anyone trying to move into the future wouldnecessarily become an _infinity_ of people--he couldn't maintain hisidentity, because he'd have to have a body in every one of an infinitenumber of places he might be--"
"--_until the normal time stream caught up with him in the future!_And then he'd be in whatever place he fit!" Roger's voice roseexcitedly. "Martin, can't you see the implications? Send meahead--just a little ahead, an hour or so--and let me go into thePalace. If I moved my consciousness to the place where the Palaceshould be, where the Dictator should be, then when normal time caughtup with me, _I could kill him_!"
Drengo was on his feet, staring at Roger with rising excitement.Suddenly he glanced at his watch. "By God!" he muttered. "_Maybe youcould_--"
* * * * *
Blackness.
He had no body, no form. There was no light, no shape, nothing buteternal, dismal, unbroken blackness. This was the Void, the placewhere time had not yet come. Roger Strang shuddered, and felt the coldchill of the blackness creep into his marrow. He had to move. Hewanted to move, to find the right place, moving with the infinity ofpossible bodies. A stream of consciousness was all he could grasp, forthe blackness enclosed everything. A sort of death, but he knew he wasnot dead. Blackness was around him, and in him, and through him.
He could feel the timelessness, the total absence of anything.Suddenly he felt the loneliness, for he knew there was no going back.He had to transfer his consciousness, his mind, to the place where theDictator was, hoping against hope that he could find the place beforetime caught him wedged in the substance of the stone walls of thePalace. He reached the place that _should_ be right, and waited--
And waited. There was no time in this place, and he had to wait forthe normal time stream. The blackness worked at his mind, filling himwith fear, choking him, making him want to scream in frightenedagony--waiting--
And suddenly, abruptly, he was standing in a brightly lighted room.The arched dome over his head sparkled with jewels, and throughpaneled windows the red glow of the city's fires flickered grimly. _Hewas in the Palace!_
He looked about swiftly, and crossed the room toward a huge door. Inan instant he had thrown it open. The bright lights of the officenearly blinded him, and the man behind the desk rose angrily, caughtRoger's eye full--
Roger gasped, his eyes widening. For a moment he thought he wasstaring into a mirror. For the man behind the desk, clothed in a richglowing tunic was a living image of--_himself!_
The Dictator's face opened into startled surprise and fear as herecognized Roger, and a frightened cry came from his lips. There wasno one else in the room, but his eyes ran swiftly to the visiphone.With careful precision Roger Strang brought the heat-pistol to eyelevel, and pulled the trigger. Farrel Strang crumpled slowly from theknees, a black hole scorched in his chest.
Roger ran to the fallen man, stared into his face incredulously. Hisson--and himself, as alike as twin dolls, for all the age difference.Drengo's words rose in Roger's mind: "Medicine is advanced, you know.People don't grow old so soon these days--"
Swiftly Roger slipped from his clothes, an impossibly bold ideatranslating itself into rapid action. He stripped the glowing tunicfrom the man's flaccid body, and slipped his arms into the sleeves,pulling the cape in close to cover the burned spot.
He heard a knock on the door. Frantically he forced the body under theheavy desk, and sat down in the chair behind it, eyes wide with fear."Come in," he croaked.
A young deputy stepped through the door, approached the deskdeferentially. "The first reports, sir," he said, looking straight atRoger. Not a flicker of suspicion crossed his face. "The attack isprogressing as expected."
"Turn all reports over to my private teletype," Roger snapped. The mansaluted. "Immediately, sir!" He turned and left the room, closing thedo
or behind him.
Roger panted, closing his eyes in relief. He could pass! Turning tothe file, he examined the detailed plans for the Martian attack; thenumbers of ships, the squadron leaders, the zero hours--then he was atthe teletype keyboard, passing on the message of peace, the message tostop the War with Mars, to make an armistice; ALL SQUADRONS AND SHIPSATTENTION: CEASE AND DESIST IN ATTACK PLANS: RETURN TO TERRAIMMEDIATELY: BY ORDER OF FARREL STRANG.
Wildly he tore into the files, ripping out budget reports,stabilization plans, battle plans, evacuation plans. It would besimple to dispose of the Dictator's body as that of an imposter, anassassin--and simply take control himself in Farrel's place. Theywould carry on with