The familiar terrain of Kant's account of the mind involves a two-fold distinction: between the two major faculties of cognition and desire, and between the higher and lower sub-faculties of each. But Kant's account of the mind contains a third major faculty that is missing from this picture--the faculty of feeling of pleasure and displeasure. Roughly, this is the faculty responsible for subjective sensation and feeling/emotion. However, at this point, a tension emerges. Just as the higher faculties of cognition and desire are identified with a function of reason, so, too, is the higher faculty of feeling. But if this is the case, does it mean that reason has or produces its own emotions? And if so, what could these emotions be like? Furthermore, wouldn't they conflict with the dichotomy thought to exist in Kant between reason and emotion (due in part to the metaphysical constraints of his theory)? In my dissertation, I argue that Kant (implicitly) conceives of emotion in functional terms. That is, emotions are evaluative judgments that initiate action. These judgments can manifest themselves in a variety of forms, depending on the objects and principles involved. This turn to a functional conception thus gives Kant the flexibility to account for emotions across a wide spectrum, from the instinctual emotions of non-rational, embodied animals to the purely rational emotions of a non-embodied god. My dissertation first develops the basic functional structure of emotion implicit in Kant's work (found especially in the Lectures on Metaphysics). It then shows the implications this cognitive structure has for understanding several central features of Kant's practical theory, including the nature of animal versus human non-moral motivation, happiness, and finally, the moral feeling of respect.