Richard Posner joins the crowd.
I guess he'll be another one who will be crossed out of your catechism and sent for a visit to your buddy Torquemada*.
I've linked to that article before but here it is again.
http://www.tnr.com/article/how-i-became ... n?page=0,0
WWHow I Became a Keynesian
Second Thoughts in the Middle of a Crisis
...
Although there are other heresies in The General Theory, along with puzzles, opacities, loose ends, confusions, errors, exaggerations, and anachronisms galore, they do not detract from the book's relevance to our present troubles. Economists may have forgotten The General Theory and moved on, but economics has not outgrown it, or the informal mode of argument that it exemplifies, which can illuminate nooks and crannies that are closed to mathematics. Keynes's masterpiece is many things, but "outdated" it is not. So I will let a contrite Gregory Mankiw, writing in November 2008 in The New York Times, amid a collapsing economy, have the last word: "If you were going to turn to only one economist to understand the problems facing the economy, there is little doubt that the economist would be John Maynard Keynes. Although Keynes died more than a half-century ago, his diagnosis of recessions and depressions remains the foundation of modern macroeconomics. His insights go a long way toward explaining the challenges we now confront. . . . Keynes wrote, ‘Practical men, who believe themselves to be quite exempt from any intellectual influence, are usually the slave of some defunct economist.' In 2008, no defunct economist is more prominent than Keynes himself."
* or from other posts in Lounge, it seems you won't even need to delegate the task of making him recant.