Guest Expert by Allen K. Lang Earth had a problem ... and the Martian visitor had a very deadly means of solving it.... [Transcriber's Note: This etext was produced from Planet Stories January 1951. Extensive research did not uncover any evidence that the U.S. copyright on this publication was renewed.] "I'm only here to help you," said the man from Mars. "You've proved that," the Secretary admitted. "In the six weeks that you've been here, you've wiped out rabies, measles, and the common cold: but sir, this latest proposal of yours is blasphemous!" The man from Mars waved an appendage in the direction of the Secretary's desk, atop which a newspaper was lying open. "After reading what that paper has to say can you still doubt that what I propose is necessary?" The young man in uniform crossed the room and picked up the newspaper. He read the headlines aloud, bitterly: "INDIAN FAMINE ARMY STORMS NEW DELHI"; "TASMAN REPUBLIC BIDS FOR PLACE IN SUN"; "PLAGUE DECIMATES LOWER NILE." "You could end that plague." The Assistant's voice was accusing. "I could, of course. The battles and the starvation would still be with you, though. Why do you persist in treating the symptoms instead of the sickness? I am an objective observer, far enough away from your problems to see them clearly, something which no human can ever hope to do. You Earthlings suffer war and famine and plague for one reason only: that there are four and eight-tenths billion of you living on an Earth which can feed only about two and a half billion of you well. Gentlemen, the population of your planet must be reduced by one-half if your race is to survive." "Couldn't we send our surplus population to Mars, or to Venus?" the Assistant asked. The man from Mars winced. "The sands of Mars can't support cactuses, much less fields of wheat and rice and corn. Venus is a solid sea of formaldehyde solution." He glanced around to each of the three men in the room. "To you, my scheme may seem heartless. But would it be more cruel to kill millions now than to allow billions to die in continual war in the next thousand years? Do you remember your last such war? The Ukrainian wheatlands scorched to desert by the thermonuclears? New England swept by epidemics of anthrax and tularemia? All China tortured by starvation and the hundred nagging sicknesses that follow hunger?" "Yes, I remember." The Secretary rolled his pen between his fingers, staring at it. "How do you intend to--liquidate--the excess two billions?" "I can't explain it to you; you lack the basic knowledge. It will be quick and painless though, I promise. Then Earth will see peace and hope; a new start!" "I couldn't take all the responsibility for this decision upon myself," the Secretary said. He glanced hopefully toward the Assistant and the young man in uniform. Their eyes flinched away.