Robert Putnam

American political scientist who popularized social capital — the civic networks and norms of reciprocity that enable collective action — and documented its decline in American life.

Making Democracy Work: social capital (civic associations, trust networks) explains why Italian regional governments perform differently — not culture but historical civic engagement. Bowling Alone: the decline of social capital in America since the 1960s — civic participation, neighborliness, and institutional trust have all declined. The Upswing: a long-run 'we'-to-'I' story of American society.