Going Underground Because of the【1】______ associations

Going Underground
   Hello, everybody! Today’s lecture is about a bold new idea —going underground to live a life in the future.
   At first thought, it may not seem a pleasant suggestion. We have so many evil associations with the underground. In our myths and legends, the underground is the realm of evil spirits and of the dead, because dead bodies are always buried underground. And the volcanic eruptions make the underground appear to be a hellish place of fire and noxious gases. It seems to be the place of an after life of torment. However, after we explore all the advantages of living underground, it may seem to be a rather appealing idea.
   The first advantage to an underground life is that weather would no longer be important. Rain, snow, fog, hurricane, all these things are only phenomena of the atmosphere, they would not trouble the underground world. Even temperature variations are limited to the aboveground world and would not exist underground. Whether day or night, summer or winter, temperatures in the underground world would remain nearly constant. The vast amounts of energy now expended in warming our surface surroundings when they are too cold, and cooling them when they are too warm, could be saved. And also the damage done to man-made structures and to human beings by weather would be gone.
   Second, local time would no longer be important. On the surface, there is always the natural and unavoidable shift between day and night. It could not be avoided that when it is morning in one place, it is noon, evening or even midnight in other places. The rhythm of human life therefore varies from place to place. While in underground, there is no externally produced day. It is artificial lighting that produces the day and this could be adjusted to suit man’s convenience. The whole world could be on an 8-hour shift, starting and ending at the same time. This is quite significant for businesses and public institutions. In a highly mobile world, the universal time shift would save travelers lots of troubles. Air transportation over long distances would no longer have to bring about "jet lag." Travelers landing on another coast or another continent would find the time of the place they reach exactly the same as at home.
   Third, the ecological structure could be stabilized. To a certain extent, it is mankind that makes the earth overcrowded. It is not only his enormous numbers that take up room; more so, it is all the structures he builds to house himself and his machines, to make possible his transportation and communication, to offer him rest and recreation. All these things distort the wild, depriving many species of plants and animals of their natural habitat. If the works of man were removed below ground, man would still occupy the surface with his farms, his forest, his observation towers, his air terminals and so on, but the extent of that occupation would be enormously decreased. Indeed, as the underground world becomes increasingly elaborate, even food could be supplied through hydroponic growth in artificially illuminated areas underground. The Earth’s surface might be increasingly turned over to park and to wilderness, maintained at ecological stability.
   Fourth, nature would be closer. It might seem that to go underground is to withdraw from the natural world, but would that be so? Would the withdrawal be more complete than it is now? Look at what we have now: We are working in crowded buildings that are often windowless and artificially conditioned; even where there are windows, and if one bothers to look up from his work and look out of the window, what is there to see? Mostly man made buildings spread all the way to the horizon. And to get away from the city, to reach the real countryside, one must travel horizontally for miles, first across downtown city and its terrible traffic, then across suburban sprawls. In an underground culture, the countryside would be right there, a few hundred yards above the city. Underground city dweller would surely be able to see more greenery —the ecologically healthier greener —than dwellers of surface cities do today.
   You see, although underground living may seem at first thought odd and repulsive, there are things to be said for it —and I haven’t said them all.