Fifteen Books:  In no particular order, here are some of my favorite mind benders. 

Charles E. Lindblom, Inquiry and Change: The Troubled Attempt to Understand and Shape Society

Karl Polanyi, The Great Transformation

Larry D. Spence, The Politics Of Social Knowledge

Eugene J. Meehan, Reasoned Argument In Social Science

Martha Nussbaum, Sex and Social Justice

Timothy D. Wilson, Strangers to Ourselves

W.E.B. DuBois, The Souls of Black Folk

Mancur Olson, The Logic Of Collective Action

Max Weber, Economy and Society

Friedrich Nietzsche, Beyond Good And Evil

Hannah Arendt, The Origins of Totalitarianism

Malcolm X, Autobiography of Malcolm X

Rachel Carson, Silent Spring

Jacques Ellul, The Political Illusion

Ralph Borsodi, This Ugly Civilization