As it is the power of exchanging that gives occasion to the division of labour, so the extent of this division must always be limited by the extent of that power, or, in other words, by the extent of the market.... There are some sorts of industry, even of the lowest kind, which can be carried on nowhere but in a great town.[7] Success, under conditions of personal competition, depends upon concentration upon some single task, and this concentration stimulates the demand for rational methods, technical devices, and exceptional skill. Exceptional skill, while based on natural talent, requires special preparation, and it has called into existence the trade and professional schools, and finally bureaus for vocational guidance. All of these, either directly or indirectly, serve at once to select and emphasize individual differences. Every device which facilitates trade and industry prepares the way for a further division of labor and so tends further to specialize the tasks in which men find their vocations. The outcome of this process is to break down or modify the older social and economic organization of society, which was based on family ties, local associations, on culture, caste, and status, and to substitute for it an organization based on occupation and vocational interests. In the city every vocation, even that of a beggar, tends to assume the character of a profession and the discipline which success in any vocation imposes, together with the associations that it enforces, emphasizes this tendency—the tendency, namely, not merely to specialize, but to rationalize one’s occupation and to develop a specific and conscious technique for carrying it on. The effect of the vocations and the division of labor is to produce, in the first instance, not social groups, but vocational types: the actor, the plumber, and the lumber-jack. The organizations, like the trade and labor unions which men of the same trade or profession form, are based on common interests. In this respect they differ from forms of association like the neighborhood, which are based on contiguity, personal association, and the common ties of humanity. The different trades and professions seem disposed to group themselves in classes, that is to say, the artisan, business, and professional classes. But in the modern democratic state the classes have as yet attained no effective organization. Socialism, founded on an effort to create an organization based on “class consciousness,” has never succeeded, except, perhaps, in Russia, in creating more than a political party.