Simmel was known as an essayist as well as author of sociological and philosophical books. Some of his major monographic One of Simmel's most widely read works, The Metropolis was originally provided as one of a series of lectures on all aspects of city life by experts in various fields, ranging from science and religion to art. The series was conducted alongside the Dresden cities exhibition of 1903. Simmel was originally asked to lecture on the role of intellectual (or scholarly) life in the big city, but he effectively reversed the topic in order to analyze the effects of the big city on the mind of the individual. As a result, when the lectures were published as essays in a book, to fill the gap, the series editor had to supply an essay on the original topic himself.