After I published Proving History a reader said I should check out Aviezer Tucker’s book Our Knowledge of the Past: A Philosophy of Historiography, since it appeared to back up the entire core thesis of my book. I am amazed and ashamed that I did not discover this book sooner. It must not have been indexed well in databases, since my searches for Bayesian historiography did not discover it. I just finished reading it, and while I wait for more opportune times to blog on other issues coming up, I thought I’d post a little about this.
Tucker is a prominent and widely published philosopher (see his bio and cv). We have at least two things in common: we both did graduate work at Columbia University, and we both think historical reasoning is fundamentally Bayesian. As some might know, the subtitle of my book is Bayes’s Theorem and the Quest for the Historical Jesus, and though the study of Jesus is its principle example, the overall thesis is that all history is Bayesian and all historians should learn Bayes’ Theorem and how to apply it to their own thinking to improve their reasoning, research, and argumentation.
Tucker makes the same argument. His approach is deeper and more philosophical, more about making the point that historical reasoning is already Bayesian, and that this explains everything from consensus to disagreement in the historical community. My book makes that argument, too, but is more about the practical application of this conclusion, and providing tools and advice for how historians can make use of Bayesian reasoning to improve what they do. Tucker delves more deeply into philosophy and probability theory and as such his book is essentially an extension of my sixth chapter (which goes into more depth on points made earlier in my book).
That’s why I regret not having known of his book before now. It’s a great shame that Proving History does not cite it, and I am writing this review now to redress that gap. OKP provides solid support for the core thesis of PH, and is the first book I know that makes the case I do (and thought I was alone in making). Others had discussed Bayes’ Theorem in the context of historical reasoning, but always skeptically or inconclusively (e.g. see PH, p. 304, n. 28). Tucker appears to be the first to understand that in fact historical reasoning is Bayesian, and to argue the point explicitly. It thus provides another foundation (and independent corroboration) for my main conclusions. It was also a prestigious peer reviewed academic work, published by Cambridge University Press in 2004 (I had my book peer reviewed as well, but my publisher is less known for that).
Owners of Proving History might want to pen Tucker’s name and book title into the margins somewhere (it should certainly have gotten a nod in note 3 of chapter four, on page 306, and probably in my discussion on page 49 as well, perhaps where I mention the precedents of applying Bayesian reasoning in law and archaeology).
The leading merits of OKP are that Tucker grounds you in the history of historiography and philosophy of history, he treats in greater detail the issues of historical consensus and disagreement (with many erudite examples), he addresses several leading problems in the philosophy of history, and he cites and adapts debates and discussions of Bayesianism in the philosophy of science and applies them to history the same way I do (only he again in more detail): by demonstrating that science and history are fundamentally the same discipline, only applied to data-sets of widely differing reliability.
As Tucker says in his central chapter (ch. 3, “The Theory of Scientific Historiography”), “I argue that the interpretation of Bayesianism that I present here is the best explanation of the actual practices of historians” and that “Bayesian formulae can even predict in most cases the professional practices of historians” (p. 134), and he gives good brief explanations of prior probability and likelihood (what I call consequent probability) in the context of historical thinking, and uses real-world examples to illustrate his point. His chapters 1 and 2 cover the background of the philosophy and epistemology of history, and remaining chapters apply the results of chapter three to address three major debates in that field: explaining disagreement among historians (ch. 4), resolving questions of causal explanation in history (ch. 5), and exploring the limits of historical knowledge and method (ch.6). He then wraps it all up with a conclusion (ch. 7). There is also an extensive bibliography and index. Throughout his book, Tucker aims to refute postmodernist and hyper-skeptical approaches to historical knowledge, and in that regard makes a good supplement to McCullagh (whom I do cite in PH).
For me, the most notable facts are that we did not know of each other, yet we independently came to the same conclusion that all historical reasoning is fundamentally Bayesian, and Tucker is a well-established philosopher and his book is by a major peer reviewed academic press. Both facts add weight and authority to my overall conclusion in Proving History. And that’s always nice to have.