The first book-length attempt to set the generic parameters of early modern revenge tragedy was also the last. Since Fredson Bowers' Elizabethan Revenge Tragedy (1940), scholarship has interrogated literary and cultural issues within the genre. But it has left intact the prevailing assumption that such plays feature revenge as their principal focus, their very reason for existing as plays. Rather than privilege the retribution trajectory as the end point of critical inquiry, my dissertation argues that revenge proved a particularly apt vehicle for engaging with the highly contested philosophies of the period. For while critical discourse has read revenge as principally concerned with matters of justice and law, the retribution motif, unique among other early modern dramatic conventions, continually recalls to audience attention both the initiating forces behind current action and the fluid boundaries between the immaterial and material. By emphasizing the relationships between cause and effect, spirit and matter, and even idea and action, early modern revenge tragedies invite reconsideration, then, of a wider range of philosophies than the legal and religious injunctions overtly invoked within such plays. Indeed, early modern revenge drama takes on, with surprising sophistication, such variegated matters as class, perceptions of moderation, the essential composition of the material world, and the generation of political power through fabulist narrative. While my individual chapters draw attention to strains of intellectual history not traditionally associated with each play - an Aristotelian faculty psychology in The Spanish Tragedy, the ethical mean in Titus Andronicus, the Lucretian atomism of Hamlet, and the Baconian fabulism of The Duchess of Malfi - my project seeks to reveal a larger point about the dynamics of revenge drama. This dissertation contends that early modern revenge tragedy emphasizes the complex interplay between the noetic, or conceptual, and the phenomenological in order to imagine, often in radical ways, the natural, ethical, and political philosophies that shape early modern culture.