This thesis sets out to examine the claims to objective reality and authentication in New critical and Structuralist literary theories, concentrating on their claims to "objectivity" and "scientific validity." It examines the nature of these claims in the light of the original ideas proposed by some of the major New critics and structuralists in the development of their respective "sciences" of literary theory. Taking direction from the nature of reality and objectivity shown by the theorists, the thesis then attempts an assessment of the validity of some of the original perceptions and presuppositions concerning scientific objectivity and reality. It proposes that inconsistencies within the literary theories resulted from the theorists' inability to grasp the complexity and fluctuating nature of the borrowed terminology and principles that they were using. It does so by taking a closer look at the development of some of the more influential physical theories and the philosophical ideas raised by these developments. It then uses Feyerabend's work on paradigms, dominance and ideology to attempt an assessment of the reasons for the literary theorists' perceptions and presuppositions regarding objectivity and reality. This amounts to accounting for the specific scientific models chosen as bases, and also to accounting for the desire for the "scientific approach" at all. Its conclusions give an indication of the extent to which these original errors contributed to the theories' necessary adaptations of perspective and eventual loss of influence, and emphasises the need for the total understanding of concepts in one field by researchers in other fields, especially if those concepts are to be used by the researchers with any degree of precision.