My most recent book was an ambitious project. I tried to be careful, and provide citations for all of my substantive claims. I also benefited from some very knowledgeable peer reviewers, and a few other experts that gave the work a once over before it went to print.
Unfortunately, a few errors did slip through the cracks, and I want to be up front about them. Most of them were mercifully very minor. I will update this as more are uncovered. I hope I do not have to make many updates.
On page 40, I accidentally referred to Young Americans for Freedom as Young Americans for Liberty. This was just a careless error on my part, as anyone who reads the book will realize that I am well familiar with the differences between the two organizations.
A bigger, and more embarrassing mistake, is that I described Hayek as being personally secular but ethnically Jewish. He was secular, but did not have Jewish ancestry -- unlike many of the other leading figures in Austrian economics. This is a very annoying error, because as I continued my research, I realized this, but forgot to go back and make the correction. I do not consider this an especially big deal, as I do not think Hayek's genealogy is relevant to his scholarship.
Justin Raimondo told me that I made some mistakes in my discussion of Murray Rothbard. He did not specify what they were, but did assure me they were "no biggie." I take his word for it that there are mistakes, as Raimondo authored an excellent biography of Rothbard. If I am given the opportunity to write a revised version of the book, I will ask him to further explain what I got wrong.
There is one possible error -- though I am pretty sure I am not actually wrong. I described Sam Francis (the paleoconservative) as non-religious. Someone on Twitter (I do not remember who) called me out on this, assuring me that Francis was a devout Presbyterian. I knew of his religious background, but it had always been my impression that he was not personally a believer, at least when he was doing his most influential writing. I am quite confident that I read something that indicates this. Unfortunately, I did not provide a citation, and in my brief look through the materials I've gathered on Francis, I could not find conclusive evidence about this one way or the other. To solve this problem, I e-mailed an acquaintance who knew Francis during his life (since I did not ask him if I could do so, I will not share his name). This is what he told me:
Sam, if I recall, had once been a devout Presbyterian but later turned into a kind of agnostic. He did however continue to think of himself as a Protestant, and his funeral service was conducted by a very traditional Presbyterian minister. His religious views have been the subject of considerable discussion. Indeed some of the paleoconservatives who converted to a pre-Vatican Two form of Catholicism have maintained that Sam underwent a conversion similar to theirs on his death bed. I find no evidence that this happened.
That does not perfectly solve the problem, of course. I still suspect that I was correct, but it was still a mistake for me to make any comment about Francis' religious beliefs without having a solid citation to back it up.
I also came very close to publishing the book with another error. In one of my final drafts, I described Tyler Cowen as being in favor of "open borders." Though Cowen is generally pro-immigration, open borders is not a fair characterization of his views. I am grateful to Bryan Caplan for catching this mistake at the last possible moment.
If anyone else has spotted any other factual errors (not typos, not problems with my interpretation of factual events), let me know and I will make note of them here.