But to speak thus is to speak what we do know. Rousseau was not open to such testimony. "My principles," he said in contempt of Grotius, "are not founded on the authority of poets; they come from the nature of things and are based on reason."[180] He does indeed in one place express his reverence for the Judaic law, and administers a just rebuke to the philosophic arrogance which saw only successful impostors in the old legislators.[181] But he paid no attention to the processes and usages of which this law was the organic expression, nor did he allow himself to learn from it the actual conditions of the social state which accepted it. It was Locke, whose essay on civil government haunts us throughout the Social Contract, who had taught him that men are born free, equal, and independent. Locke evaded the difficulty of the dependence of childhood by saying that when the son comes to the estate that made his father a free man, he becomes a free man too.[182] What of the old Roman use permitting a father to sell his son three times? In the same metaphysical spirit Locke had laid down the absolute proposition that "conjugal society is made by a voluntary compact between man and woman."[183] This is true of a small number of western societies in our own day, but what of the primitive usages of communal marriages, marriages by capture, purchase, and the rest? We do not mean it as any discredit to writers upon government in the seventeenth century that they did not make good out of their own consciousness the necessary want of knowledge about primitive communities. But it is necessary to point out, first, that they did not realise all the knowledge within their reach, and next that, as a consequence of this, their propositions had a quality that vitiated all their speculative worth. Filmer's contention that man is not naturally free was truer than the position of Locke and Rousseau, and it was so because Filmer consulted and appealed to the most authentic of the historic records then accessible.[184]