At its publication, the book received different responses and caused a debate national wide. The book received great popularity among American people of different walks of lives and became a best seller immediately. David Watt, a literary critic, said “No American novel published in this century has aroused such a storm as The Grapes of Wrath did. One has to go back to Uncle Tom’s Cabin to witness its equal.”(Wyatt 2) The Grapes of Wrath is regarded the most exemplary indictment about the myth of California as a Promised Land. Its appearance permanently changed the literary geography of the America. The novel was awarded the Pulitzer Prize in 1940 and then was adapted to the screen. In 1962, Steinbeck was awarded the Nobel Prize for Literature largely because of The Grapes of Wrath which proved itself to be one of the most enduring works of fiction by any American author, past and present. Although he published many other books, Steinbeck’s prestige and significance was mainly gained by The Grapes of Wrath.

2.2 Previous Researches on the Grapes of Wrath
Since the publication of the book of The Grapes of Wrath, there emerged many conflicting opinions about the nature and quality of this book. Because it was not just a fictional novel, but also was a story which described the miserable experience of the landless peasants and the national picture during the period of the Great Depression. Today, readers often find fault with its excessive sentimentality and generally flat characterizations, which seem at odds with Steinbeck’s otherwise realistic style of writing. However, the large majority of readers and scholars praised the novel highly. Numerous researches have discussed the book from different perspectives. Some focused on the studies of its characters and their dialect. Some analyzed the artistic features of prose styles and symbolic meanings. Some, by applying the theories of ecocriticism through systematic analysis of the book, tried to reveal the theme of Steinbeck’s ecological thoughts. And also, some centered on the creative interchapters scattered in the book and the phenomenal ending of the book. Some were interested in the economic and political cultures, closely connected to the history background of the time of The Great Depression, for the landless workers. Another important research approach is the philosophical studies of the migrant workers.

Paul B. Thompson (2007), who regards The Grapes of Wrath as a history of politics and of economy, centers upon the political culture and the philosophy of the working class. He argues that Steinbeck was implying political theory of an egalitarian or utilitarian view. The characters of the novel endure a time of trial in which selfishness gives way to altruism, to a sense of the greater whole. The embrace of factory-worker class mentality is never explicit. The lingering notion is that if each inpidual would simply embrace altruism, all would be resolved. That lingering, implicit theme is what made the book seem to be sentimentally optimistic to those who were trying to bring factory-style organized labor to the fields of California. The events of The Grapes of Wrath turn on the uneven contest between the itinerant Okies and the various representatives of the property owning class they confront. The bankers and large California farmers get no sympathy from Steinbeck, but the events of the novel demand that we understand their worldview. That worldview comes directly out of 17th century British philosophy typified by Locke. The central ethical concepts are personal liberties and property rights, both of which are understood as instances of non-interference rights. The economic structure of US agriculture has undergone a drastic transition since 1900. At the beginning of the 20th century, approximately 70% of Americans lived on farms. At the beginning of the 2nd millennium, the number stands at 3% (Paul, 2006). While many forces have influenced this transition, the unwanted loss of a farm home through bankruptcy and eviction-the events that befall the Joads-has not been atypical. Many more families have abandoned farming voluntarily when they saw that such a fate lay in store. The economic force and events that precipitated the Joads’ plight are not recounted in the novel, but two ideas from economic theory explain what might have happened in the way that is entirely consistent with Steinbeck’s text. 浅析《愤怒的葡萄》中失土农民的抗争历程(3):http://www.youerw.com/yingyu/lunwen_9912.html