This thesis attempts to answer one basic question: what we can philosophically say to justify liberalism as a mode of political existence of society. It is divided into three parts. In the first one, I critically survey two popular answers to this question, employing the concepts of self- ownership and value pluralism respectively. I argue that both of them are inadequate and unsatisfactory, mostly because they operate with a conception of person that is too thin for the justificatory task. In the second part, I develop an interpretation of John Rawls and the conception of person he uses. I argue that this conception is crucial with regards to his answer to my question, yet that he provides only a limited and in the final analysis unpersuasive justification for it. The third part tries to remedy the deficiencies of Rawlsian liberalism by providing a better argumentative support for his conception of person and developing from it two arguments aiming to justify liberalism as a mode of political existence of society Key words Liberalism - John Rawls - Pluralism - Conception of person