Like many I've found the quality of our decision making process to be extremely poor during the pandemic – around subjects like masks, social distancing, and vaccines.

Some of this low quality reasoning has come from experts who should have known better. A common error is for an expert to say there is 'no evidence' for something (e.g. that masks work), when really what they mean is that there is no randomized control trial that answers the specific question being asked.

But of course during a fast-moving pandemic, we don't always have time to do large scale RCTs for every intervention. We need to make decisions, and to do nothing is also a decision that can have serious costs. We need to be able to consider cost/benefit tradeoffs of the options available to us even if we don't have perfect information. Of course, one of the options on the table is to take no action until we have more information. But the fact that this option also has costs has to be considered.

Robert Wiblin has a great thread on this 'no evidence' fallacy: