And we must realize that the State is not and has never been sovereign, because sovereignty means a natural right (which does not belong to the State but to the body politic as perfect society) to a supreme power and independence which are supreme separately from and above the whole that the sovereign rules (and of which enither the State nor the body politic is possessed). If the State were sovereign, in the genuine sense of this word, it could never surrender its sovereignty, nor even have it restricted. Whereas the body politic, which is not sovereign, but has a right to full autonomy, can freely surrender this right if it recognizes that it is no longer a perfect society, and decides to enter a larger, truly perfect political society.
Jacques Maritain, Man and State, Catholic University of America Press (Washington, D.c., 1998), p. 195. 'Perfect' here is not used axiologically but descriptively, i.e., to indicate a complete whole.