Second, on the contrary, some critics criticize Sister Carrie from the perspective of moral ethics. They argue that Carrie is “the fallen woman” because she is amoral, driven by her desire for material success. For example, Liu Yumei’s paper, The Analysis of Theodore Dreiser’s Style from the Love Affairs in Sister Carrie, analyzes the love affairs of Carrie. When with Drouet, there is some traditional believes in her deep heart for her insisting on the relationship being based on marriage; while when with Hurstwood, Carrie showed her selfishness totally. She elopes with him when he is wealthy and decent, and leaves him for his sink[Liu& Chen,2010]. They examine Carrie’s change in attitudes towards marriage, sex and success. “It is Carrie’s philosophy that she only saves herself —the most precious property her body for the highest bidder. Sex should be paid for and it is conditional. [Liu& Chen, 2010]” The desire-driven and unconventional girl is seen as “the fallen woman”. Deng Xiaoyu and Xie Qiueng interpret Sister Carrie from the three elements, human nature, desire and instinct, on which Dreiser’s moral viewpoint is based（Deng& Xie, 2010）. They examine the human behavior through these aspects. Carrie’s behavior is a mixed consequence of the three aspects. 

Third, there have been researches about women under the commercial culture. At the turn of the 19th and 20th centuries, America turned into a spendthrift and consumptive commercial society. This phenomenon is well reflected in Dreiser's novel Sister Carrie. Chen Yu and Li Qingqun’s Consumption Culture in Sister Carrie [2012], probes into the consumption culture, in particular, the features of material consumption, emotion consumption and body consumption. The thesis describes Carrie as a firm advocate and finally a sacrifice of the consumption culture. It reveals the human spiritual crisis and the social viciousness in the money-oriented capitalist society. The scene of Carrie sitting in the rocking chair actually indicates the void of consumption culture [Chen& Li, 2012]. Also, there are scholars who testify the rotten way of consumption. HO Nia, FT Baghbaderani, in Consumer Culture in Theodore Dreiser’s Sister Carrie, “attempt to examine the dexterity of Dreiser in portraying the inner and outer lives of characters in such a society and in light of Baudrillard’s theory of consumerism and the way this portrait approximates real life [Helen& Fatemeh, 2012]”. In their opinion, people live in an industrial and commodified society in which people find their identity in items of consumption. Carrie is not only a protagonist of a novel, she is rather a reflection of modern people and we’d better learn from her experience. 

1.2 Thesis Statement 

The previous researchers have analyzed the novel in each perspective, or partly attached to other perspectives. Though feminism is a focus of criticism, only a few of the scholars have analyzed deeply from the Eco-feminist perspective. Some of the papers relate Sister Carrie to Eco-feminism talking about the deterioration of environment, the dependence of female, and the benefit-connected interpersonal relationship. Zhang Mao, in his paper, viewing from the perspective of eco-feminism, shows the limitation of the novel and ascribes the limitation to the shadow of Dreiser’s time [Zhang, 2014]. Liu Yi’s paper, An Eco-feminist Comparison between Sister Carrie and My Antonia[2014], argues that Sister Carrie embodies the struggles and triumphs of women in the 19th and most of the early 20th century, and the struggle that Carrie undergoes is an expression of the underlying constraints that the paternal and chauvinistic society of her time places upon both women and the natural world. It focuses on how the feminine aspect of nature faces and overcomes suppression. So it further explains that “Carrie conforms to the chauvinistic way of thinking and displays it herself [Liu, 2014]”. “This is seen in the way she treats those around her who helped her rise to fame but who she later shuns and discards in a chauvinistic show of independence and a disapproval of squalor. [Liu, 2014]” And we can see Liu Yi is not so approval of the way female rise up to against male. As for the possible solution to the crisis of ecological ethics, Zhu Zhenwu, in Sister Carrie: A City Immigrant in Crisis of Ecological Ethics [2006], investigates this novel from the angle of spiritual ecology and feminist ethnics, claiming that “in today's world that is still dominated by men and characterized by unprecedented material production, the importance of ecological ethics should be reevaluated and resurrected as a spiritual redemption for human beings' returning to nature and ethic [Zhu, 2006]”.  《嘉莉妹妹》的生态女性主义解读(3):http://www.youerw.com/yingyu/lunwen_50801.html