This theory was, we have seen, a commonplace. The amount of historical authenticity assigned to the contract almost universally presupposed varied enormously. Generally, the weaker a writer's rational basis, the more he appealed to history--and invented it. It was, therefore, almost inevitable that Rousseau should cast his theory into the contractual form. There were, indeed, writers of his time who laughed at the contract, but they were not writers who constructed a general system of political philosophy. From Cromwell to Montesquieu and Bentham, it was the practically minded man, impatient of unactual hypotheses, who refused to accept the idea of contract. The theorists were as unanimous in its favour as the Victorians were in favour of the "organic" theory. But we, criticising them in the light of later events, are in a better position for estimating the position the Social Contract really took in their political system. We see that Locke's doctrine of tacit consent made popular control so unreal that he was forced, if the State was to have any hold, to make his contract historical and actual, binding posterity for all time, and that he was also led to admit a quasi-contract between people and government, as a second vindication of popular liberties. Rousseau, on the other hand, bases no vital argument on the historical nature of the contract, in which, indeed, he clearly does not believe. "How," he asks, "did this change [from nature to society] come about?" And he answers that he does not know. Moreover, his aim is to find "a sure and legitimate rule of administration, taking men as they are and laws as they might be"; that is to say, his Social Contract is something which will be found at work in every legitimate society, but which will be in abeyance in all forms of despotism. He clearly means by it no more and no less than the fundamental principle of political association, the basis of the unity which enables us, in the State, to realise political liberty by giving up lawlessness and license. The presentation of this doctrine in the quasi-historical form of the Social Contract theory is due to the accident of the time and place in which Rousseau wrote. At the same time, the importance of the conception is best to be seen in the hard death it dies. Though no-one, for a hundred years or so, has thought of regarding it as historical, it has been found so hard to secure any other phrase explaining as well or better the basis of political union that, to this day, the phraseology of the contract theory largely persists. A conception so vital cannot have been barren.