Inequality and philanthropy: Author of ‘The Givers’ explains how they can fuel each other

American philanthropy has been undergoing a major resurgence in the last few decades, leading some to dub this a 'golden age' for giving. At the same time, wealth concentration and inequality, the gap between rich and poor, has been on the increase. Author of a new book called The Givers, David Callahan, explains why these two trends are fueling each other and what needs to change to avoid oligarchy.