> There is no "uncertain marginal effect." The science is in, and it's clear. Statements like this help no one. "The science" is not a noun. It is not "in". Th

> There is no "uncertain marginal effect." The science is in, and it's clear. Statements like this help no one. "The science" is not a noun. It is not "in". There is a great deal of uncertainty in what we actually know about masks. The article you're claiming is definitive proof admits as much: "being more definitive about how well they work or when to use them gets complicated. There are many types of mask, worn in a variety of environments. There are questions about people’s willingness to wear them, or wear them properly. Even the question of what kinds of study would provide definitive proof that they work is hard to answer." Again, please read the Lancet, CEBM and DANMASK links I linked above. You will see that there is a great deal of uncertainty.