According to many opinions, John Rawls is one of the most significant political philosophers of 20th century, whose famous work A theory of justice, in which he introduces his readers to his theory known as justice as fairness, is based on the philosophical thought of Immanuel Kant. His mentioned concept, also known as a form of political liberalism erupted throughout the world as a most adequate concept of justice for liberal-democratic society permeated by cultural pluralism. Nevertheless, in his further philosophical development, Rawls comes to the conclusion that his theory is not entirely correct, that is, the ideas set in the Theory are inconsistent because they are recognized as unrealistic for the society for which they are intended. In his next famous work, Political liberalism and in his article Kantian constructivism in moral theory, Rawls finds a solution for this problem precisely in abandoning Kantian philosophy. In Political liberalism Rawls seperates the concept of justice as fairness from moral philosophy and presents it as an exclusively political concept. The idea behind Kantian constructivism is unacceptable for Rawls because it is based on the transcendental concept of a person and society, implying that all equal members of a democratic society share the same comprehensive view of justice. Due to this, Rawls abandons the Kantian constructivism and introduces us with his new theory of political constructivism.