Sociability is a concept that reflects not only the individual's ability to enter into social communication, but also the dependence of the structure of social interaction on the degree of the individual's freedom in society. Kant's ethics arguably represents a key stage in the development of this idea. However, it was not until a later era that a comprehensive notion was formed according to which the social actualisation of individual freedom is a significant factor in social development. The Russian neo-Kantian, Sergey Hessen, develops a model of sociability where education forms free individuals who exercise their freedom through the development of culture. I reconstruct Hessen's model and establish that, proceeding from Rickert's axiology, he showed how education can improve the realisation of the ideals of freedom and equality in the framework of Kant's individualistic treatment of society. In his pedagogical philosophy, Hessen identifies stages in human development (anomie–heteronomy–autonomy), in the course of which the individual renounces arbitrariness. Hessen stresses the crucial significance of the secondary school in developing an awareness of freedom as duty and of society as the sphere of its actualisation. In his legal theory, Hessen strips the state of its law-making function and distributes that to the whole society. This enables free individuals to accept the need for universal subjection to the law under conditions of equality. Hessen proposes a new social structure: individuals create collective entities, each of which forms its own legal order, while the state coordinates these legal orders to prevent conflict and contradictions among them.