The Middle Ages is not noted for its scientific knowledge and achievement. For one thing,

medieval philosophy suffered from the dictation of the Church. It was merely an endeavor to give a scientific statement of medieval theology. Another thing that hindered the progress of science in the Middle Ages was a misrepresentation of, and a lavish devotion to, Aristotle. His theories were accepted by medieval men as pure gold, and his writings were regarded as a bible. So they became a roadblock to scientific progress.

However, in the 13th century, there appeared a few scholars who criticized the habit of relying on Aristotle for all knowledge. The most distinguished of them was Roger Bacon, an English monk and philosopher. Bacon declared that even if Aristotle were very wise he had only planted the tree of knowledge and that this had "not as yet put forth all its branches nor produced all its fruits." He held that truth could be reached a hundred thousand times better by experiments with real things than by poring over the bad Latin translation of Aristotle.

Bacon was interested in any subject that he thought could broaden man' s understanding of the world. He made many important discoveries and speculated about such things as gunpowder, flying machines, telescopes, and mechanically driven carriages. Greater than any of these was the scientific method that he employed. The most far-sighted of his beliefs was that observation and experiment are essential to an understanding of nature. He was one of the forerunners of the experimental and applied science of modern times.

It was not until the 17th century that the scientific method championed by Roger Bacon was set forth anew and rendered fruitful by Francis Bacon and Descartes.

Francis Bacon was the most eloquent representative of the new science which renounced authority and relied upon experiment. In his Advancement of Learning, he urged that men should cease to rely upon the textbooks, like Aristotle, and turn to a careful examination of animals, plants, and chemicals, with a view of learning about them and using the knowledge thus gained to improve the condition of mankind.

Descartes, French philosopher and mathematician, was interested in many subjects. Throughout his varied career he held fast to the conviction that science depends no; upon the authority of ancient books but upon the observation of facts. Once, pointing to a basket of rabbits that he was about to dissect, he told a visitor, "Here are my books." He could not see any reason why the old authorities should be right. So he boldly set to work to think out a wholly new philosophy that was entirely the result of his own reasoning.

As can be gathered from the passage, Aristotle's theories ______ in the Middle Ages.

A．were ignored by most scholars

B．hindered scientific progress

C．were declared as heresy

D．were basis of important discoveries