In terms accessible to non-economists, Marcos Jose Mendes describes the ways democracy and inequality produce low growth in the short and medium terms. In the longer term, he argues that Brazil has two paths in front of it. One is to create the conditions necessary to boost economic performance and drive the country toward a high level of development. The other is to fail in untying the political knot that blocks growth, leaving it a middle-income country. The source of his contrasting futures for Brazil is inequality, which he demonstrates is a relevant variable in any discussion of...