GRE考试老外写作范文——Issue 138.

　　"Only through mistakes can there be discovery or progress."

　　The speaker contends that discovery and progress are made only through mistakes. I strongly agree with this contention, for two reasons. First, it accords with our personal experiences. Secondly, history informs us that on a societal level trial-and-error provides the very foundation for discovery and true progress, in all realms of human endeavor.

　　To begin with, the contention accords with our everyday experience as humans from early childhood through adulthood. As infants we learn how to walk by falling down again and again. As adolescents we discover our social niche, and develop self-confidence and assertiveness, only by way of the sorts of awkward social encounters that are part-and-parcel of adolescence. Through failed relationships not only do we discover who we are and are not compatible with, we also discover ourselves in the process. And, most of us find the career path that suits us only through trying jobs that don&apost.

　　This same principle also applies on a societal level. Consider, for example, how we progress in our scientific knowledge. Our scientific method is essentially a call for progress through trial-and-error. Any new theory must be tested by empirical observation, and must withstand rigorous scientific scrutiny. Moreover, the history of theoretical science is essentially a history of trial-and-error. One modern example involves two contrary theories of physics: wave theory and quantum theory. During the last quarter-century scientists have been struggling to disprove one or the other--or to reconcile them. As it turns out, a new so-called "string" theory shows that the quantum and wave theories are mistakes in the sense that each one is inadequate to explain the behavior of all matter; yet both so-called "mistakes" were necessary for physics to advance, or progress, to this newer theory.

　　The value of trial-and-error is not limited to the sciences. In government and politics, progress usually comes about through dissension and challenge--that is, when people point out the mistakes of those in power. In fact, without our challenging the mistaken notions of established institutions, political oppression and tyranny would go unchecked. Similarly, in the fields of civil and criminal law, jurists and legislators who uphold and dend legal precedent must face continual opposition from those who question the fairness and relevance of current laws. This ongoing challenge is critical to the vitality and relevance of our system of laws.

　　In sum, the speaker correctly asserts that it is through mistakes that discovery and true progress are made. Indeed, our personal growth as individuals, as well as advances in science, government, and law, depends on making mistakes.