Book excerpt: This book offers a new introduction to the thought of Gabriel Tarde, highlighting the continuing relevance, and even the novelty, of both his general theoretical approach and many of his specific analyses. Showing that Tarde elaborates a comprehension of the social that was received with difficulty in his time but is increasingly akin to ours, it demonstrates that the infinitesimal sociology offered to us by Tarde provides a framework through which we can understand a whole range of social phenomena. With attention to social networks, public opinion, innovation, diffusion, virality and virtuality—all of which were topics addressed by Tarde himself—the author clarifies and elaborates upon Tarde’s central theses on the multiple, differential, infinitesimal and infinite nature of both the social and the subjective. An examination of the importance of a figure whose work looked ahead to our own age, Reintroducing Gabriel Tarde will appeal to scholars and students of social sciences and social theory with interests in contemporary social thought.