The State, in this conception has but three functions--defence, justice and "the duty of erecting and maintaining certain public works and certain public institutions which it can never be for the interest of any individual, or small number of individuals, to erect and maintain." The State, in fact, is simply to provide the atmosphere in which production is possible. Nor does Smith conceal his thought that the main function of justice is the protection of property. "The affluence of the rich," he wrote, "excites the indignation of the poor, who are often both driven by want and prompted by envy to invade their possessions. It is only under the shelter of the civil magistrate that the owner of that valuable property, acquired by the labor of many years, or perhaps many successive generations, can sleep a single night in security." The attitude, indeed, is intensified by his constant sense that the capital which makes possible new productivity is the outcome of men's sacrifice; to protect it is thus to safeguard the sources of wealth itself. And even if the State is entrusted with education and the prevention of disease, this is rather for the general benefit they confer and the doubt that private enterprise would find them profitable than as the expression of a general rule. Collective effort of every kind awakened in him a deep distrust. Trade regulations such as the limitation of apprenticeship he condemned as "manifest encroachment upon the just liberty of the workman and of those who may be disposed to employ him." Even educational establishments are suspect on the ground--not unnatural after his own experience of Oxford--that their possibilities of comfort may enervate the natural energies of men.