Using an Aristotelian model, this thesis tracks the use of probability, evidence, and belief as types of rhetorical proof in Shakespearean criticism. Probabilistic argument, largely absent from eighteenth-century literary criticism, provides the basis for modern stylometric studies, and these studies' use of statistical and rhetorical probability demonstrate rhetorical absences in eighteenth-century criticism. Edmond Malone, eighteenth-century editor of Shakespeare, uses documentary evidence in new ways which place him in the category of textual scholar as defined by D.C. Greetham, and his departure from Aristotle's advice against evidence has significant effects on his critical rhetoric. Belief, both as doxa and as devotion, enlivens and directs critical rhetoric. Finally, logical, enthymematic argument, which is often missing from Shakespearean criticism, serves as a method of compromise between an unbalanced reliance on proof, and the pedantry of pure syllogistic reasoning.