While the two modernist novels considered in this book, Samuel Beckett's Murphy and Malcolm Lowry's Under the Volcano, were initially understood within the categories of stoic and tragic despair, more recent criticism has focused upon their carnivalesque dimension. The identification of these hermeneutic polarities presented the author with the challenging problem which underlies the present analysis, namely the question concerning the structural relationship between the contesting thematics. Drawing upon the paradigm of oscillation as established within the natural sciences, and adding a figurative dimension to the concept, the author has adapted this model as a key to unravelling the narrative buoyancy and structural coherence which sustain these novels of Modernism. The book elucidates how the carnivalesque challenge to despair contributes towards innovative narrative configurations, galvanizing the thematic antipodes into vertiginous microcosms of defiant selfhood.