Unless I am much mistaken we have here the key to the whole democratic system of government evolved by Jefferson and the solution of the apparent contradictions often pointed out in his system. Starting from the hypothesis of Hobbes that in a state of nature men are free agents and have no other law but their own will, Jefferson attributes to the surrounding dangers the urge to form some sort of a society, a theory also found in Locke. But what follows is more original: in forming a social compact, men do not abdicate all their sovereignty as in the hypothesis of Rousseau; they do not even abdicate a certain portion of all their rights. On the contrary, they reserve entire a certain class of rights, all those they can exercise fully without the aid of exterior assistance, and they exchange for more security those they cannot exercise themselves. Thus the social compact is no longer a _pactum subjectionis_. It is no longer a question of deciding whether in a society the individual or the society are sovereign, since both are sovereign in their respective domains. How far Jefferson was from being a demagogue is clearly indicated by the sentence in which he refers to James Wilson. Liberty, except liberty of speech and thought, cannot be unlimited and unrestricted in any society; it is a matter of bargain and exchange. Thus Jefferson proposed a definition of liberty entirely different from the French conception as found in Rousseau and reproduced in the "Déclaration des droits de l'homme" of May 29, 1793: "_La liberté consiste à pouvoir faire tout ce qui ne nuit pas à autrui._" With him, on the contrary, liberty consists in the free enjoyment of our will except in certain specific cases, to be enumerated at the time we form a social compact. Hence the necessity of a Bill of Rights, in which the individual accepts certain limitations in order to obtain a corresponding amount of security, and specifically denominates those of his natural rights he means to keep integrally and wholly.