Modern philosophy is often seen as characterized by a shift of focus from the things themselves to our knowledge of them, i.e., by a turn to the subject and subjectivity. The philosophy of Immanuel Kant is seen as the site of the emergence of the idea of a subject that constitutes the object of knowledge, and thus plays a central role in this narrative. This study examines Kant’s theory of knowledge at the intersection between the history of science and the (...) history of the modern subject, on the one hand, and in the tension between modern experimental and mathematical science and more traditional Aristotelian conceptions of epistemic perfection, on the other. The dissertation consists of four chapters. In the first chapter, I examine Kant’s concept of experience, and its relation both to Early Modern experimentalism and to the Wolffian tradition. In the second chapter, I argue that Kant adheres to a broadly Aristotelian conception of epistemic perfection – the ideal of understanding – but transforms this ideal into the self-understanding of reason, where reason can only have insight into the products of its own activity. In the third chapter, I use Kant’s conception of space and time to exemplify such products of reason, and argue that, for Kant, space and time are constructively generated representations that function as principles for ordering empirical knowledge. In the fourth and final chapter, I examine Kant’s conception of the subject, and situate it in relation to both the long history of the modern subject and German Enlightenment philosophy. Whereas the modern philosophical conception of the subject is usually taken to combine an ‘I’ functioning as the subject to which mental acts are attributed and an ‘I’ that has the ability to immediately perceive itself as the subject of these acts, I argue that Kant reconceives this relation between the ‘I’ and its acts as a purely intellectual self-relation. The unity of the ‘I’ is not a perceived unity, but a unity brought about by the intellect. (shrink)