In contrast to all animals who can only passively adjust to nature's requirements by finding a niche in the ecological order that allows them to subsist and develop, man is active in relation to his surroundings. He fashions tools with which to transform his natural habitat. Men "begin to distinguish themselves fro animals as soon as they begin to produce their means of subsistence. . . . In producing their means of subsistence men indirectly produce their actual material life."

Men "who every day remake their own life" in the process of production can do so only in association with others. This is what makes man a zoon politicon. The relations men establish with nature through their labor are reflected in their social relationships.

The production of life, both of one's own by labor and of fresh life by procreation, appears at once as a double relationship, on the one hand as a natural, on the other as a social relationship. By social is meant the cooperation of several individuals, no matter under what conditions, in what manner or to what end. It follows from this that a determinate mode of production, or industrial stage, is always bound up with a determinate mode of cooperation, or social stage, and this mode of cooperation is itself a 'productive force.'
In their struggle against nature, and to gain their livelihood through associated labor, men create specific forms of social organization in tune with specific modes of production. All these modes of social organization, with the exception of those prevailing in the original stage of primitive communism, are characterized by social inequality. As societies emerge from originally undifferentiated hordes, the division of labor leads to the emergence of stratification, of classes of men distinguished by their differential access to the means of production and their differential power. Given relative scarcity, whatever economic surplus has been accumulated will be preempted by those who have attained dominance through their expropriation of the means of production. Yet this dominance never remains unchallenged. This is why "the history of all hitherto existing society is the history of class struggles."

Free men and slaves, patricians and plebeians, barons and serfs, guildmasters and journeymen, exploiters and exploited have confronted one another from the beginning of recorded time. Yet Marx, insisted on the principle of historical specificity, that is, he thought it essential to note that each particular class antagonism, rooted in particular productive conditions, must be analyzed in its own right. Each stage in history is conceived as a functional whole, with its own peculiar modes of production, which give rise to distinctive types of antagonisms between exploiting and exploited classes. Not all exploited classes have a chance to assert themselves in successful combat against their exploiters. The revolts of the slaves of antiquity or of the German peasantry at the time of the Reformation were doomed to failure because these classes did not represent a mode of production that would dominate in the future. On the other hand, the bourgeoisie in the last stages of feudalism and the proletariat in modern times were destined to be victorious since they represented a future mode of production and social organization.

While Marx can be considered a historical evolutionist, it would be a mistake to think of him as a believer in unilinear evolution. He was acutely aware of periods of relative stagnation in human history--for example, in Oriental societies--and he knew of historical situations characterized by a stalemate, a temporary equilibrium, between social classes. His writings on the regime of Napoleon III illustrate in masterful fashion a historical situation in which the forces of the old class order and of the new are so nearly balanced that neither is able to prevail, thus giving rise to a "Bonapartist" stalemate. Moreover, though throughout his life Marx held fast to the belief that the future belongs to the working class, which will lead the way to the emergence of a classless society, he was nevertheless willing to consider the possibility that the working class may not be equal to its "historical task" so that mankind would degenerate into a new kind of barbarism.

Marx conceived of four major successive modes of production in the history of mankind after the initial stage of primitive communism: the Asiatic, the ancient, the feudal, and the modern bourgeois form. Each of these came into existence through contradictions and antagonisms that had developed in the previous order. "No social order ever disappears before all the productive forces for which there is room in it have been developed; and new higher relations of production never appear before the material conditions of their existence have matured in the womb of the old society."

Class antagonisms specific to each particular mode of production led to the emergence of classes whose interests could no longer be asserted within the framework of the old order; at the same time, the growth of the productive forces reached the limits imposed by previous productive relations. When this happened, the new classes, which represented a novel productive principle, broke down the old order, and the new productive forces, which were developed in the matrix of the old order, created the material conditions for further advance. However, "the bourgeois relations of production are the last antagonistic form of the social process of production." When they have been overthrown by a victorious proletariat, "the prehistory of human society will have come to an end," and the dialectical principle that ruled the previous development of mankind ceases to operate, as harmony replaces social conflict in the affairs of men.

Marx's emphasis on the existential roots of ideas, his stress on the need to view thinking as one among other social activities, has remained--no matter what qualifications have to be made--one of the enduring parts of his work. Together with his economic interpretation of the course of human history, his theory of class relations, and his focus on the alienating aspects of social life in modern society, it has become a permanent part of the sociological enterprise.

From Coser, 1977:55-57.