P.D. Jonson, Great Crises of Capitalism (Connor Court, 2011), 322 pages, $29.95.  Many readers of Quadrant will already be familiar with Dr P.D. Jonson. A former Chief Economist of the Reserve Bank of Australia, now a corporate director, Jonson is also the eponymous founder of the Henry Thornton website, which hosts commentary on economics, politics and current events from a broad spectrum of liberal opinion. Perhaps Jonson’s principal claim to significance was his role in persuading Paul Keating to float the dollar, a defining moment in the history of Australia. In his current book, Great Crises of Capitalism, Jonson offers…