The aim of this thesis is to lay the ground for further work on interpreting Coleridge’s Logic and its relation to the rest of his philosophy, particularly the system of speculative metaphysics and theology presented in Coleridge’s Opus Maximum fragments. I do this by exploring the connections between Coleridge’s conceptions of the a priori, the cognitive faculties (or capacities), and the nature of logical theory. Part 1 seeks to place Coleridge’s views on logic in their broader historical and intellectual context, showing why Coleridge considered the investigation of the faculties, and the analysis of our cognitive operations and contents, to be fundamental to logical theory, and arguing that this position is a product of Coleridge’s critical engagement with the early modern logic of ideas and faculties. Part 2 gives a preliminary account of Coleridge’s interpretation of two key Kantian terms, ‘a priori’ and ‘transcendental’, exploring the analogies Coleridge uses to elucidate the nature of the a priori and the purpose of transcendental claims. Part 3 expands on this account, considering how Coleridge’s conceptions of the a priori and the transcendental inform his claims, especially in Logic, on the human mental faculties and their contribution to sensory experience and cognition; it focuses on Coleridge’s views on ‘the obvious threefold division’ of our cognitive capacities into sense, understanding, and reason, his descriptions of the formal (a priori) and material (a posteriori) elements of cognition, and his functional theory of the constitution of our faculties. Part 4 discusses the relations between Coleridge’s theory of the cognitive capacities and his conception of the a priori, focusing on Coleridge’s claims concerning the origins of a priori forms and contents in our cognitive capacities, and the transcendental method of inquiry which he contends is able to prove such claims.