或许给它提供最系统的定义的使豪斯（House）（1977）。豪斯的目的是为评估翻译质量提供方法，因此，她的功能对等概念基本上评价性的。她（1944：42）提出了一种详细的。“多维度”文本功能分析，区分三种涉及语言使用者的语言用法维度（“地理来源”、“社会等级”与“时间”），还区分了五个反映语言使用的维度（“中介”、“参与”、“社会角色关系”、“社会态度”与“领域“，或一般话语范围）。运用这一框架，就有可能为源文本与目标文本建立一个“文本数据图”。豪斯指出，译本“不仅在功能上要切合源文本，而且应该采用对等的情景维度以取得这一功能”（1977：49）。这意味着，如果要想目标文本在功能上与源文本达到对等，那么，在相关文本关系特别密切的多个维度上，源文本与目标文本应当彼此高度对应（1977：49）。在豪斯所提范围更广的模式内，功能对等只有在隐型翻译[Covert Translation]的情况下才能实现（1977：204），但是，“因为必须要考虑到社会文化规范的差异”（1977：205），因此，即使在这里功能对等仍难以实现。然而，按照格特的观点，在文本具有多个功能的情况下，问题仍然存在（1991：10）；实际上，建立一个能够适应这类文本的模式是及其困难的。应该指出，功能对等这一术语也被得·瓦得（de Waard）与奈达（Nida）（1986）用来取代奈达在别处成为动态对等[Dynamic Equivalence]的概念；按照得·瓦得与奈达的观点，这一术语不那么容易被人误解，而且使用它可以“强调翻译的交际功能”（1986：ⅷ）。
Polysystem Theory
Itamar Even-Zohar ( 佐哈尔)， born in 1939 in Tel Aviv, Israel, is a researcher of culture and professor of Poetics and Comparative Literature of the Unit of Culture Research, Tel Aviv University. Even-Zohar’s integral contribution is internationally known as the polysystem theory and the theory of cultural repertoires, which gave rise to a line of research areas.
He has been developing the polysystem theory designed to deal with dynamics and heterogeneity in culture concentrating on interactions between various cultures. In earlier stages of his work, he contributed to developing a polysystemic theory of translation, designed to account for translation as a complex and dynamic activity governed by system relations rather than by a priori fixed parameters of compatative language capabilities. This has subsequently led to studies on literay interference, eventually analyzed in terms of intercultural relations.
The literay traditions generally perceive the translated texts as a cultural intruder, a carrier of foreign values to that particular cultural system. When a culture is stable and self-sufficient, translated literature holds a peripheral position and imported items have to be presented as compatible with the indigenous tradition for acceptability. Then target acceptability-oriented translation strategies are most likely used. On the other hand, translation is usually undertaken for the purpose of bringing about new ideas or changes. In the situation when a literay polysystem is young, weak or in crisis, translated literature may assume a central position, as a cultural tool, taking part “in the process of creating new, primary models” （Even-Zohar 1990a：
50）Thus translated literature holds a more central position when a system is weak and in need of forces from other cultures in order to fill in cultural gaps or to legimate the existing structures of power, and when the foreign text contributes to reinforce esthetic or ideological valuse already present within the system and becomes instrumental to the establishment or reinforcement of cultural values. Due to the conception of translation as a supplementary activity or a secondary product, translation appears to have a secondary function in the polysystem of the target culture. Translation can be viewed as a means by which a culture influences another culture, introducing new and foreign impulses in the target culture.
The term “polysystem” refers to the entire network of correlated systems, liteary and extra-literary within a society. For exploring intra-systemic literay relations, Even-Zohar posited in 1978 the notion of polysystem for the aggregate of literary systems including all canonized and non-canonized forms in a given culture, based on his recognition of the importance of translated literature in liteary history. He developed an approach as polysystem theory to attempt to explain the functions of the all kinds of writing within a give culture and his analysis demonstrated that translated literature functions differently depending upon the age, strenth, and atability of the particular polysystem (Gentzler 1993:114-115)
Within a literary polysystem, there exists a hierarchical structure of differing subsystems, which are different types of literature---canonized, non-canonized, and translated literature. They constantly struggle for a more central position than others to maintain a primary position in the culture rather than the secondary position. This competition leads to a dynmic, ongoing process of literary mutation and evolution. The role translated literature plays in the culture is either central or peripheral, primary or secondary. If it occupies a primary positon, it participates actively in shaping the centre of the polysystem ( Even-Zohar 1987,as cited in Munday 2001:110). It may serve for innovations in the liteary history and may set up new models in the target culture. If it assumes a secondary position, it represents a peripheral system within the polysystem and conforms to the established literary norms and conventional forms of the target culture. Even-Zohar suggests that the position occupied by translated literature in the polysystem conditions the translation strategy (ibid.). If it is primary, the translator is more concerned with the linguistic and cultural feutures of the source text to produce an adequate translation, whereas if it is secondary, the translator is prepared to emphasize the literary conventions and cultural features of the target system. He also suggests that the relationship between translated literature and the literary polysystem is dependent upon the specific socio-cultural, historical circumstances operating within the literary system ( Gentzler 1993:117) He observes the position of translation within varying cultural systems to determine how texts to be translated are
selected by the receiving culture and how translated texts adopt certain norms and functions as a result of their relation to other target language systems ( Even-Zohar 1978, as cited in Gentzler 1993:118) .Polysystem theory is therefore revised to include extraliterary factors, socio-cultural forces such as patronage, social conditions, economics, and institutional manipulation correlated to the way tranaslations are chosen and function for the cultural turn in translation studies that further enhanced the development of Western translation theories.