Introduction / C. Mantzavinos -- Part I : basic problems of sociality -- Language and social ontology / John R. Searle -- Comment : de rerum natura : dragons of obliviousness and the science of social ontology / Mark Turner -- Shared agency / Michael E. Bratman -- Comment : where is the social? / Pierre Demeulenaere -- The reality of group agents / Philip Pettit -- Comment : a note on group agents / Diego Rios -- Part II : laws and explanation in the social sciences -- Pysicalism and the human sciences / David Papineau -- Comment : reductionism in the human sciences : a philosopher's game / Robert Shulman and Ian Shapiro -- Complexity and explanation in the social sciences / Sandra Mitchell -- Comment : conditional knowledge : an oxymoron? / James Alt -- The heterogeneous social : new thinking about the foundations of the social sciences / Daniel Little -- Comment : causal mechanisms and generalizations / Jack Knight -- What is this thing called "efficacy"? / Nancy Cartwright -- Comment : randomized controlled trials and public policy / Gerd Gigerenzer -- Part III : how philosophy and the social sciences can enrich each other : three examples -- Why do people cooperate as much as they do? / James Woodward -- Comment : putting the problem of social order into perspective / Werner Güth and Hartmut Kliemt -- Situations against virtues : the situationist attack on virtue theory / Ernest Sosa -- Comment : do people have character traits? / Steven Lukes -- What kind of problem is the hermeneutic circle? / C. Mantzavinos -- Comment : going in circles / David-Hillel Ruben -- Epilogue / C. Mantzavinos.