Shin, I'm a fan and I look forward to your next articles.

But I'm not a fan of this specific article. First, the lab leak theory is no less scientific than the zoonotic origin theory. I know more than one highly accomplished epidemiologist who strongly believes in the lab leak theory, because of the evidence. These are scientists who publish in Cell, Nature, PNAS, etc. They know about zoonoses, they know about lab leaks, and they know about biodefense work.

So there was no win for science vs. some other agenda. Each side has good scientific credentials.

Second, I find the methodology flawed. The calculation for P0 (LL) involves a large chain of individual steps each with an attached probability. The more steps, the lower the probability. The calculation for P0 (Z0) involves very few steps. This discrepancy alone accounts for the results. The same problem affects the Drake equation for the likelihood of extraterrestrial life.

In general, as you know, a probability is a sum of probabilities for individual paths, each of which can be expressed as a product. Having only one term in the product implies that you have carved up the steps in a way that each sum is buried in a single probability per step. This is a very difficult thing to do. I think it's next to impossible.

Specifically, I think there's at least one other path to the lab leak which is much more probable than the one chosen. That is: the observed mutations need not have been engineered by design. They could have been engineered by artificial evolution. I think that's much more plausible. The investigators wanted to see if virulence/transmissability could be amplified by selection in a "natural setting." That's the question I would have asked (except that I don't believe gain-of-function research should ever be done). And if you do that, P0(LL) may become comparable, if not larger, than P0(Z0).

I also find the ratio of prior probabilities suspect. Ask for the probability that this pandemic occurred in the vicinity of the largest, and recently opened, BSL-4 facility in the world. Seems rather unlikely to me. So I think the ratio used is too low.

Further, I think the dismissal of reports of sickness of Wuhan researchers in fall/winter 2019 is unjustified. I remember reading such reports at the time -- before the word COVID or pandemic entered the news.

Again, I deeply appreciate your articles and will continue to read them avidly.