题目内容
The invention of both labor-saving tools and tools of intelligence is rarely accidental. Instead, it is usually the product of human need; (1) is truly the mother of invention. People usually devise tools to (2) for natural deficiencies. For example, people invented weapons to defend (3) from physically superior (4) . But (5) is only one incentive for inventions. People also invent (6) tools to (7) certain established tasks more efficiently. For instance, people developed the bow and arrow from the (8) spear or javelin in order to shoot (9) and strike with greater strength.(10) civilizations developed, greater work efficiency came to be demanded, and (11) tools became more (12) . A tool would (13) a function until it proved (14) in meeting human needs, at which point an improvement would be made. One impetus for invention has always been the (15) for speed and high-quality results—provided they are achieved (16) reasonable costs. Stone pebbles were sufficient to account for small quantities of possessions, (17) they were not efficient enough for performing sophisticated mathematics. However, beads arranged systematically evolved into the abacus. The (18) of this tool can be (19) to the development of commerce in the East around 3000 B.C. and the abacus is known (20) by the ancient Babylonians, Egyptians, Chinese, etc.. 18（）
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Passage ThreeIt is hard to predict how science is going to turn out, and if it is really good science it is impossible to predict. If the things to be found are actually new, they are by definition unknown in advance. You cannot make choices in this matter. You either have science or you don’t, and if you have it you are obliged to accept the surprising and disturbing pieces of information, along with the neat and promptly useful bits.The only solid piece of scientific truth about which I feel totally confident is that we are profoundly ignorant about nature. I regard this as the major discovery of the past hundred years of biology. It is, in its way, an illuminating piece of news. It would have amazed the brightest minds of the 18th century Enlightenment to be told by any of us how little we know and how bewildering seems the way ahead. It is this sudden confrontation with the depth and scope of ignorance that represents the most significant contribution of the 20th century science to the human intellect. In earlier times, we either pretended to understand how things worked or ignored the problem, or simply made up stories to fill the gaps. Now that we have begun exploring in earnest, we are getting glimpses of how huge the questions are, and how far they are from being answered. Because of this, we are depressed. It is not so bad being ignorant if you are totally ignorant; the hard thing is knowing in some detail the reality of ignorance, the worst spots and here and there the not-so-bad spots, but no true light at the end of the tunnel nor even any tunnels that can yet be trusted.But we are making a beginning, and there ought to be some satisfaction. There are probably no questions we can think up that can’t be answered, sooner or later, including even the matter of consciousness; to be sure, there may well be questions we can’t think up, ever, and therefore limits to the reach of human intellect, but that is another matter. Within our limits, we should be able to work our way through to all our answers, if we keep at it long enough, and pay attention. The author believes that （）.
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