BRAVERMAN emphasizes that merchandise and currency establish interchange of relations in capitalist production, but that the rocks angular are the sales and purchase of force of 12 work. For in such a way, it affirms, three basic conditions become generalized: initially, the separation of the workers of the ways with which the production is carried through (they only can have access to these means of production vendendo its force of work) 13; after that, the freedom of the workers whom it makes possible to them to make use of its force of work; finally, the intention of the job of the worker becomes it expansion of a unit of the pertaining capital the employer. These three conditions demonstrate that the work process starts through a contract that stipulates the conditions of sales of determined force of work for the worker and its respective purchase for the employer. The diligent one firms the contract because another alternative of survival does not remain it. The employer wants to extend its unit of capital and for in such a way he does not hesitate in converting part of this capitalem wages.
This relation, however, it demands some reflections. The work, as any vital process is inalienable of the individual. Thus, as it is not possible to drink, to eat or to sleep for another person, also it is not to separate to muscles or brain to it of people. Of this form the employer cannot assume itself of the capacity of work of the worker, he lucratively holds back but it to fixes it in the work. He has a historical character in this phenomenon. The sales and purchase of the work force already occurred in the 14 seniority, but after century XIV wage-earning workers they had only started to appear with bigger emphasis in the Europe. They had become significant and numerically important after the advent of the Industrial Revolution, in century XVIII, under the regency of different relations of the found ones in the mercantilism, marked for the exchange of exceeding products.