It would obviously be impossible to reduce the ideas of such an irregular thinker to systematic form. In later years Proudhon himself confessed that ‘the great part of his publications formed only a work of dissection and ventilation, so to speak, by means of which he slowly makes his way towards a superior conception of political and economic laws.’ Yet the groundwork of his teaching is clear and firm; no one could insist with greater emphasis on the demonstrative character of economic principles as understood by himself. He strongly believed in the absolute truth of a few moral ideas, with which it was the aim of his teaching to mould and suffuse political economy. Of these fundamental ideas, justice, liberty, and equality were the chief. What he desiderated, for instance, in an ideal society was the most perfect equality of remuneration. It was his principle that service pays service, that a day’s labour balances a day’s labour—in other words, that the duration of labour is the just measure of value. He did not shrink from any of the consequences of this theory, for he would give the same remuneration to the worst mason as to a Phidias; but he looks forward also to a period in human development when the present inequality in the talent and capacity of men would be reduced to an inappreciable minimum. From the great principle of service as the equivalent of service he derived his axiom that property is the right of _aubaine_. The _aubain_ was a stranger not naturalised; and the right of _aubaine_ was the right in virtue of which the Sovereign claimed the goods of such a stranger who had died in his territory. Property is a right of the same nature, with a like power of appropriation in the form of rent, interest, etc. It reaps without labour, consumes without producing, and enjoys without exertion. Proudhon’s aim, therefore, was to realise a science of society resting on principles of justice, liberty, and equality thus understood; ‘a science, absolute, rigorous, based on the nature of man and of his faculties, and on their mutual relations; a science which we have not to invent, but to discover.’ But he saw clearly that such ideas, with their necessary accompaniments, could be realised only through a long and laborious process of social transformation. As we have said, he strongly detested the prurient immorality of the schools of Saint-Simon and Fourier. He attacked them not less bitterly for thinking that society could be changed off-hand by a ready-made and complete scheme of reform. It was ‘the most accursed lie,’ he said, ‘that could be offered to mankind.’