The article discusses how innovation and social change happen within social networks, focusing on the concepts of cohesion and hierarchy. It explores the importance of understanding when and where innovations occur, as well as why they happen in certain contexts. By using network approaches, the researchers aim to measure the strength and nature of connections within groups, as well as the impact of hierarchy on agency. The goal is to integrate formal mathematical theories with social science theories to better understand how different types of innovation unfold in complex social and historical dynamics.