The brief (accelerated) summary of the thesis of his book "Social Acceleration; A New Theory of Modernity" begins in the video @ 20 min. In that book he adds a fifth wheel to the four traditional elements that have dominated sociological analysis of modernity, namely 1) the rationalization (instrumentalizing) process as expounded by Max Weber and Habermas, 2) the differentiation ( e.g.division of labor) associated with Emile Durkheim, 3) the social tendency towards individualization thematized by Georg Simmel, and 4) the processing and transformation of nature and character ( e.g .commodification) which constituted the starting point for the analysis of modernity for Karl Marx and those who followed him ( e.g. Horkheimer and Adorno).These tendencies are actually the modes of functioning or manifestations of the 'fifth wheel": social accelerations, in Hartmut's analysis. It cuts across all four cornerstones of the 'classical' analytical grid.The book is an attempt to sharpen our view of the complexity of the modernizing process.All this is quite difficult to summarize adequately (instrumentally) within the obvious limitations of this blog. But his analysis of such (objective and subjective) empirical data that IS available regarding A) technical acceleration, B) the acceleration of social change and C) the acceleration of the pace of life is fascinating and worth struggling through the dense theoretical framework of the book. I expect to publish a few interesting examples in subsequent blogs.