It has been argued that the relation between sovereignty and the universal will is an important ontological and legal postulate because the commonality is an integral attribute of law. The agreement is not just an institution in the legal system but also a legal attribute that places a mutual obligation on its parties. The content of such legal attributes as justice freedom equality hierarchy without generality is only the content of ideas because if justice is not understood equally by everyone the law will flow into the sphere of relativity. If power can originate only from the universal origin, and the only plural that can produce this universal is the population then it is obvious that the nation as a sovereign are absolute. The article explores the doctrine of J.-J. Rousseau's of people's sovereignty. The author analyzes how this doctrine reveals the inherent attributes of legal being: generality and agreement. It is argued that the principle of the universal will of the people's will which is the basis of popular sovereignty is one of the foundations of legal existence because individual law at its extremes leads to destructive processes. In order to realize the principle of generality another legal attribute is needed the contract as laid down by human nature's capacity for mutual restrictions. The author concludes that the link between lawmaking and universal will is not just a principle of democracy it is an ontological link. The individual as a part cannot dominate the general, because then there is no reason for the binding of the result of its activity. People's power is nothing more than the result of the unfolding of the legal attribute of community in human being. From Rousseau's doctrine the author summarizes that the content of legal attributes is concentrated in the general will and if they retain their true meaning in different socio-political modes then the principle of democracy is possible even in the monarchy. The value of the Rousseau principle of people's power which argued that the universal will is the only source of power without intermediaries is not in the ideals to be pursued but in the legal understanding of political processes.