While it's hard to argue that it runs in the family to some extent in this case, David Friedman is an econ thinker in his own right and certainly goes way further into what most would call extreme libertarian/"uber-rational econ" territory than Milton Friedman ever did. In fact, I'd say that "The Machinery of Freedom" ought to entitle David Friedman to the simpler introduction "...because the author is David Friedman."