For me, scientific knowledge is divided into mathematical sciences, natural sciences or sciences dealing with the natural world (physical and biological sciences), and sciences dealing with mankind (psychology, sociology, all the sciences of cultural achievements. every kind of historical knowledge).
Apart from these sciences is philosophy, about which we will talk later. In the first place, all this is pure or theoretical knowledge, sought only for the purpose of understanding, in order to fulfill the need to understand that is intrinsic and con-substantial to man. What distinguishes man from animals is that he knows and needs to know. If man did not know that the world existed, and that the world was of a certain kind, that he was in the world and that he himself was of a certain kind, he wouldn’t be man. The technical aspects or applications of knowledge are equally necessary for man and are of the greatest importance, because they also contribute to defining him as man and permit him to pursue a life increasingly more truly human.
But even while enjoying the results of technical progress, man must defend the primacy and autonomy of pure knowledge. Knowledge sought directly for its practical applications will have immediate and foreseeable success, but not the kind of important result whose revolutionary scope is for the most part unforeseen, except by the imagination of the Utopians. Let me recall a well-known example. If the Greek mathematicians had not applied themselves to the investigation of conic section zealously and without the least suspicion that it might someday be useful, it would not have been possible centuries later to navigate far from shore. The first men to study the nature of electricity could not imagine that their experiments, carried on because of mere intellectual curiosity, would eventually lead to modern electrical technology, without which we can scarcely conceive of contemporary life.
Pure knowledge is valuable for its own sake, because the human spirit cannot resign itself to ignorance. Butt in addition, it is the foundation for practical results that would not have been reached if this knowledge had not been sought disinterestedly.
Why is electrical technology mentioned in the third paragraph（）
A.To confirm its importance in the modern world
B.To show the powerful influence of its inventions
C.To verify the usefulness of theoretical knowledge
D. To give an example of success in practical science
参考答案：C
解析：
[注释] 逻辑结构题。本题问：为什么第3段中提到电气技术第3段第1句是段落主题句，它写道：“但是即使人类在享受技术进步的成果时，他也必须维护理论知识的首要性和自主性。”这是本段的论点。接着作者以对圆锥体和电的理论研究来证明理论知识的有用性，即理论科学是应用科学的基础。可见正确答案非[C]莫属。 [D]是强干扰项，属就事论事、偏离主题；其他选项之所以不能入选是因为没有说明论据与论点之间的逻辑关系。此类题很重要，明年必考。
