You should proofread the passage on the Answer Sheet and correct it in the following way: There are great many reasons for studying what philosophers have said 79. ______ in the past. One is that we cannot separate the history of philosophy from which 80. ______ of sciencE. Philosophy is largely discussion about matters on which few people are 81. ______ quite certain, and those few hold opposite opinions. As knowledge increases, Philosophy buds off the sciences. For an example, in the ancient world and 82. ______ the Middle Ages philosophers discussed motion. Aristotle and St. Thomas Aquinas taught that a moving body would slow down until a force were 83. ______ constantly applied to it. They were wrong. It goes on moving unless some-thing slows it down. But they had good arguments on their side, and if we study these, and the experiments which proved them right, this will help 84. ______ us to distinguish truth from false in the scientific controversies of today. We 85. ______ also see how different philosopher reflects the social life of his day. 86. ______ Plato and Aristotle, in the slave-owning society of ancient Greece, thought man's highest state was contemplation rather than activity. In the Middle Ages St. Thomas believed a regular feudal system of nine ranks of 87. ______ Angels. Herbert Spencer, in the time of free competition between capitals, found the key to progress the survival of the fittest. Thus Marxism is seen to fit into its place as the philosophy for the workers, the only class with a futurE.88. ______ (74)