A branch of Marxism that---following Marx, Karl’s own prescription---takes the position that the development of history is not determined by the desire or actions of specific human subjects, but is instead shaped by the objective facts of material existence. History unfolds as the attempt by humans to alter their natural environment to suit their particular needs---this explains, in part, why technology developed at a faster pace in colder climates, the need to defend against the environment was much greater there than in, say, the tropics, where the climate is more congenial. In order to meet their needs humans must work together and produce not only the specific goods they need but society itself. In doing so, however, divisions between different groups of people whose interests differ arise, the result of which is social antagonism. These groups, which might have been artisans, farmers or merchants to begin with, evolve into class, of which there are three basic types: landowners, bourgeoisie (i.e. manufacturers and merchants), and workers. The relationship between the classes is dialectic according to Marx inasmuch as their respective interests do not coincide. The working through of this dialectic is referred to as class struggle. Further Reading: P. Anderson In the Tracks of Historical Materialism (1983).