Book IV, Chapter II
It may be seen, from the last chapter, that the way in which general business is managed may give a clear enough indication of the actual state of morals and the health of the body politic. The more concert reigns in the assemblies, that is, the nearer opinion approaches unanimity, the greater is the dominance of the general will. On the other hand, long debates, dissensions and tumult proclaim the ascendancy of particular interests and the decline of the State.
This seems less clear when two or more orders enter into the constitution, as patricians and plebeians did at Rome; for quarrels between these two orders often disturbed the comitia, even in the best days of the Republic. But the exception is rather apparent than real; for then, through the defect that is inherent in the body politic, there were, so to speak, two States in one, and what is not true of the two together is true of either separately. Indeed, even in the most stormy times, the plebiscita of the people, when the Senate did not interfere with them, always went through quietly and by large majorities. The citizens having but one interest, the people had but a single will.
At the other extremity of the circle, unanimity recurs; this is the case when the citizens, having fallen into servitude, have lost both liberty and will. Fear and flattery then change votes into acclamation; deliberation ceases, and only worship or malediction is left. Such was the vile manner in which the senate expressed its views under the Emperors. It did so sometimes with absurd precautions. Tacitus observes that, under Otho, the senators, while they heaped curses on Vitellius, contrived at the same time to make a deafening noise, in order that, should he ever become their master, he might not know what each of them had said.
On these various considerations depend the rules by which the methods of counting votes and comparing opinions should be regulated, according as the general will is more or less easy to discover, and the State more or less in its decline.
There is but one law which, from its nature, needs unanimous consent. This is the social compact; for civil association is the most voluntary of all acts. Every man being born free and his own master, no-one, under any pretext whatsoever, can make any man subject without his consent. To decide that the son of a slave is born a slave is to decide that he is not born a man.
If then there are opponents when the social compact is made, their opposition does not invalidate the contract, but merely prevents them from being included in it. They are foreigners among citizens. When the State is instituted, residence constitutes consent; to dwell within its territory is to submit to the Sovereign. 
Apart from this primitive contract, the vote of the majority always binds all the rest. This follows from the contract itself. But it is asked how a man can be both free and forced to conform to wills that are not his own. How are the opponents at once free and subject to laws they have not agreed to?
I retort that the question is wrongly put. The citizen gives his consent to all the laws, including those which are passed in spite of his opposition, and even those which punish him when he dares to break any of them. The constant will of all the members of the State is the general will; by virtue of it they are citizens and free.  When in the popular assembly a law is proposed, what the people is asked is not exactly whether it approves or rejects the proposal, but whether it is in conformity with the general will, which is their will. Each man, in giving his vote, states his opinion on that point; and the general will is found by counting votes. When therefore the opinion that is contrary to my own prevails, this proves neither more nor less than that I was mistaken, and that what I thought to be the general will was not so. If my particular opinion had carried the day I should have achieved the opposite of what was my will and it is in that case that I should not have been free.
This presupposes, indeed, that all the qualities of the general will still reside in the majority: when they cease to do so, whatever side a man may take, liberty is no longer possible.
In my earlier demonstration of how particular wills are substituted for the general will in public deliberation, I have adequately pointed out the practicable methods of avoiding this abuse; and I shall have more to say of them later on. I have also given the principles for determining the proportional number of votes for declaring that will. A difference of one vote destroys equality; a single opponent destroys unanimity; but between equality and unanimity, there are several grades of unequal division, at each of which this proportion may be fixed in accordance with the condition and the needs of the body politic.
There are two general rules that may serve to regulate this relation. First, the more grave and important the questions discussed, the nearer should the opinion that is to prevail approach unanimity. Secondly, the more the matter in hand calls for speed, the smaller the prescribed difference in the numbers of votes may be allowed to become: where an instant decision has to be reached, a majority of one vote should be enough. The first of these two rules seems more in harmony with the laws, and the second with practical affairs. In any case, it is the combination of them that gives the best proportions for determining the majority necessary.
 This should of course be understood as applying to a free State; for elsewhere family, goods, lack of a refuge, necessity, or violence may detain a man in a country against his will; and then his dwelling there no longer by itself implies his consent to the contract or to its violation.
 At Genoa, the word Liberty may be read over the front of the prisons and on the chains of the galley-slaves. This application of the device is good and just It is indeed only malefactors of all estates who prevent the citizen from being free. In the country in which all such men were in the galleys, the most perfect liberty would be enjoyed.