## 2013 WSC, Hong Kong

**A**fter an early but taxing morning run overlooking the city, and a recovery breakfast (!), I went from my flat to the nearby Hong Kong Convention Centre where the ISI (2013 WSC) meeting is taking place. I had a few chats with friends and publishers (!), then read a chapter of Rissanen’s book over an iced coffee before attending the Bernoulli session. This was a fairly unusual session with a mix of history of probability, philosophy of probability and statistics, and computational issues (my talk). Edith Sylla gave some arguments as to why *Ars Conjectandi* (that she translated) was the first probability book ever. Krzys Burdzy defended his perspective on why von Mises and de Finetti were wrong (in their foundational views of statistics). And I gave my talk on a mixture of Bernoulli factory, Russian roulette and ABC (After my talk, Victor Perez Abreu told me that Jakob Bernoulli had presumably used simulation to evaluate the variance of the empirical mean in the Bernoulli case.) What I found most interesting in the historical talk was that Bernoulli had proven his result in the late 1680’s but he waited to complete his book on moral and commercial issues, waited too long since he died before. This reminded me of Hume using probabilistic arguments a few years later to disprove the existence of miracles. And of Price waiting for Bayes’ theorem to counter Hume. The talk by Krzys was a quick summary of the views exposed in his book, which unsurprisingly did not convince me that von Mises and de Finetti (a) had failed and (b) needed to use a new set of (six) axioms to define probability. I often reflected on the fact that when von Mises and de Finetti state(d) that probability *does not exist*, they applied the argument to a single event and this does not lead to a paradox in my opinion. Anyway, this talk of Krzys’ induced most of the comments from the floor, my own talk being *in fine* too technical to fit in this historical session. *(And then there was still some time to get to a tea shop in Sheng Wan to buy some Pu Ehr, if not the HK$3000 variety…!)*

August 28, 2013 at 1:54 pm

In my understanding, by “probability does not exist” De Finetti simply means that probability is not an ontological phenomenon that exists per se (like the mass of the electron) but rather it is an assigned hence epistemological quantity. I think that all Bayesians would agree on this, so no sure why KB thinks de Finetti got it wrong…

(well, what he did get wrong is that he rejected countable additve probabilty, but that is another story).

August 29, 2013 at 10:43 pm

I completely agree!