Harold Bloom's critical work involves a systematic attempt to unify rhetoric and psychology into a theory which provides an account of the nature, aetiology and structuring principles of influence in Post-Renaissance poetry. The thesis examines the development and context of those theories, seeing them partly as an initially mythologised response to structuralist thought which is modified and meliorated in later work. The theories themselves are examined, including the argument for the unity of psychology and rhetoric, the historical account Bloom provides, and his arguments on the nature of influence-relations. It is argued that the attempt to link psychology and textual material results in a distorted account of these various topics which ignores the complexity both of actual influences and of texts. It results also in disunities within Bloom's work between psychological and rhetorical perspectives, and between progressive and retrospective formulations for literary creation. His practical criticism is examined and found to loosely apply his theories but to operate more by a suggestive intertextuality. It supports his own myths only by a considerable distortion of its subject and by a selective blindness. Finally, Bloom's stance and metatheoretical claims are examined. This stance is both polemical and empirical, claiming to unify the two by a duplication of the stance of Romantic poets which also initiates a levelling of discourse. Consequently his theories are reflexive. However this reflexivity 1oes not constitute proof, and Bloom's claims to empirical status ultimately deconstruct his mimetic stance because of the presence of a hermeneutics which depends on a privileged position. His theories thus never achieve the coherency they argue for.