This psychological balance which every individual was supposed to carry within himself, and which, as the basis of the Neo-Classical school, is known as the Hedonistic principle, is admirably described by Quesnay.[24] “To secure the greatest amount of pleasure with the least possible outlay should be the aim of all economic effort.” And this was what the “order” aimed at. “When every one does this the natural order, instead of being endangered, will be all the better assured.” It is of the very essence of that order that the particular interest of the individual can never be separated from the common interest of all, but this happens only under a free system. “The movements of society are spontaneous and not artificial, and the desire for joy which manifests itself in all its activities unwittingly drives it towards the realisation of the ideal type of State.”[25] This is _laissez-faire_ pure and simple.[26] These famous formulæ have been so often repeated and criticised since that they appear somewhat trite to-day. But it is certain that they were not so at the time. It is easy to laugh at their social philosophy, to mock at its _naïveté_ and simplicity, and to show that such supposed harmony of interests between men does not exist, that the interests of individuals do not always coincide with those of the community, and that the private citizen is not always the best judge even of his own interests. It was perhaps necessary that the science should be born of such extreme optimism. No science can be constructed without some amount of faith in a pre-established order. Moreover, _laissez-faire_ does not of necessity mean that nothing will be done. It is not a doctrine of passivity or fatalism. There will be ample scope for individual effort, for it simply means leaving an open field and securing fair play for everyone, free from all fear lest his own interests should injure other people’s or in any way prejudice those of the State. It is true that there will not be much work for the Government, but the task of that body will by no means be a light one, especially if it intends carrying out the Physiocratic programme. This included upholding the rights of private property and individual liberty by removing all artificial barriers, and punishing all those who threatened the existence of any of these rights; while, most important of all, there was the duty of giving instruction in the laws of the “natural order.” II: THE NET PRODUCT