The reason this book is important is that he's shown the r > g idea with data. As Picketty mentions in that article, it's a field of research that's an "academi

The reason this book is important is that he's shown the r > g idea with data. As Picketty mentions in that article, it's a field of research that's an "academic no-man's land." It's traditionally too "economic" for history and too "historical" for economics. Marx was espousing a theory. He wrote a manifesto. This is based on data that no one else has bothered to look into.