I’m continually appalled by how easily people move from “the consequences of doing X are uncertain” to “X must be banned!”, even when there would seem every reason to expect that X actually has high expected value and ought to be encouraged, if anything.The latest example is X = J&J booster shots for the immunocompromised (or, indeed, everyone):The weasel words there ‘isn’t enough data to determine’ indicate a typical failure to think in Bayesian terms and use all the information available and a typical failure to think in terms of patient welfare and expected cost and benefits.Notice also the illiberal default. Instead of saying ‘we don’t have data on the J&J vaccine and the immunocompromised so we are not at this time recommending or not recommending boosters but leaving this decision in the hands of patients and their physicians’ they say ‘we don’t have data and so we are forbidding patients and their physicians from making a decision using their own judgment.’It’s an ongoing problem in our pandemic response that prudent precautionary measures like this get blocked, without any positive medical justification, because the Powers That Be don’t follow decision theory and instead insist that we all must sit passively on the tracks, ignoring the oncoming train, while they order routine safety checks on the service ladder.Apologies for sounding like a broken record on this, but this problem of pandemic paralysis is (i) really serious, and (ii) insufficiently appreciated. So it’s worth repeating again: mere uncertainty is not sufficient reason to reject a pandemic policy proposal. Critics need to offer reasons for thinking that the potential downsides outweigh the potential upsides (in expectation).For an extended version of the argument (with many real-world examples), see my paper: ‘Pandemic Ethics and Status Quo Risk’. It argues at length for the banal — and yet almost universally rejected or neglected — claims that (1) it. . .