Simmel conceives sociology as the science of social forms (in a sense affording form analytic primary over content - although in reality they are inseparable). He makes use of a helpful analogy of geometry as the study of forms (ie. shapes) which may exist in an unlimited variety of physical materials. Simmel believes that sociology should leave the examination of the content of societal interaction to other sciences (such as psychology or economy) in the way that geometry leaves content analysis to the physical sciences.
Simmel views exchange as the purest and most concentrated form of significant human interaction. In fact, much action that may initially appear to be unilateral actually involves reciprocal effects (ie. is a form of exchange) and generally all interactions may more-or-less be conceived of as exchange. One characteristic of exchange is that the sum of values (of the interacting parties) is greater afterward than it was before - ie. each party gives the other more than he had himself possessed.
The commercial emporium of the world city expositions framed Simmel's view of the metropolis as the nexuspoint for the circulation of capital, commodities, and people. That commerce was central to the great transformations of modernity was not lost upon Marx in his writings on the political economy of capital, but was Simmel exploared in this essay as well as his magnum opus, The Philosophy of Money, were the philosophical and psychological dimensions of money in modern culture. Simmel discussed the triumph of the city as a sensorium of psychic overstimulations and commodity temptations.
Georg Simmel stands in the unusual position of being the only European scholar who has had a palpable influence on sociology in the United States throughout the course of the 20th century. This is particularly noteworthy in view of the fact that, contrary to current impressions about the history of the discipline, when sociology was becoming established within the American academic system during the first few decades of this century, it was truly a homegrown project.
Simmel observes that because of their peculiar position in the group, strangers often carry out special tasks that the other members of the group are either incapable or unwilling to carry out. For example, especially in pre-modern societies, most strangers made a living from trade, which was often viewed as an unpleasant activity by "native" members of those societies. In some societies, they were also employed as arbitrators and judges, because they were expected to treat rival factions in society with an impartial attitude.
Simmel obtained his doctorate of philosophy in 1881 at the University of Berlin. Marginalized by the German academic system because of Jewish ancestry and intellectual radicalism, Simmel did not obtain a regular academic appointment until the last four years of his life. For most of his career, he maintained a recurring lecturing position at the University of Berlin, where his lectures influenced an extraordinary legacy of students, including Georg Lukacs, Ernst Bloch, Karl Mannheim and Robert Park.
From 1885 to 1900, he was a Privatdozent (a lecturer un- paid except for student fees) in philosophy, and for another fourteen years, an ausserordentlicher Professor ("professor extraordinary," an honorary, but not a remunerative title) both at the University of Berlin. In 1914, at the age of 56, four years before his death, he was called to Strasbourg as a full professor (Or dinar ius). He died on September 26, 1918.
Simmel also was interested in the conflicts between the individual and social structures, but his greatest concern was the conflicts that develop between individual culture and objective culture. He perceived a general process by which objective culture expands and individual culture becomes increasingly impoverished in the face of this expansion. Simmel saw this conflict, in turn, as part of a broader philosophical conflict between more-life and more-than-life.
His status as an outsider may have contributed to his wide range of interests and innovative thought. He published more than 200 articles and over a dozen books in several social science fields. As a generalist, Simmel did not inspire a particular school of thought or methodology.
Simmel was best known for his work on smaller-scale issues, especially individual action and interaction. He became famous early for his thinking, derived from Kantian philosophy, on forms of interaction and types of interactants. Basically, Simmel saw that understanding interaction among people was one of the major tasks of sociology.