Investigation of Kant's critique of practical reason in the context of enlightenment ideal

Enlightenment is a universalist conception of being an intellectual movement passing beyond of time and space, an ethos in the sense of regulating life with reason, and a form of struggle against all obstacles to development. The Enlightenment, which intensified in the eighteenth century and gave its name to an age with its revolutionary features, caused great changes in the individual and society with the effect of these features. Undoubtedly, the Enlightenment philosopher Immanuel Kant is the one who contributed the most to the philosophical realization of these changes. Therefore, the aim of this thesis, which intends to deal with the relations between Enlightenment Thought and Practical Reason, is to show the ties of his practical philosophy to the Enlightenment thought through examination of Kant's works, especially his Critique of Practical Reason. For this purpose, in the first part of the study, which consists of three chapters, besides the explanation of the general character of the Enlightenment Age, Kant's understanding of Critical Reason, which is an important contribution to Enlightenment, is examined and the theoretical basis of Kant's practical philosophy is shown. In the second part, Kant's idea of autonomy, which is the keystone of his philosophical system, is proved to be a fundamental condition of Enlightenment. In the third and last chapter, the effect of practical reason is examined where Kant's ideas are embodied in a system that goes from individual to universality. As a result of this study, it is concluded that by the reason of Kant's ethical understanding is in harmony with the Enlightenment ideal and that Enlightenment is a project that has not been completed yet, it can offer a different perspective to today's problems. At the same time, it has been tried to show that Kant's practical ideas that manifest theirselves in his Idea of Enlightenment have the potential to fill the void in the moral field today. Keywords: Enlightenment, Critical Reason, Practical Reason, Autonomy, Freedom, Categorical Imperative, Morality, Cosmopolitan Citizenship.