OK, Nigel, I was lazy enough to try the aphorism without checking the right wording, but I got quite close!

As I've repeatedly said in another thread, Donuel (which you'd be wise to confine yourself to, in my humble opinion), the mask evidence you refer to is purely observational. Not only is that potentially far weaker than experimental evidence (which in this case we can't have for ethical and practical reasons), it is also extremely vulnerable to confounding factors. You accuse others of linear thinking. What I've just said is the polar opposite of that. In fact, evangelical mask advocacy such as yours, in the absence of reliable evidence, is a great example of the linear thinking that you so ironically accuse others of resorting to.

I said evangelical mask advocacy (the sort of thing that has mask sceptics being accused of being Nazis or of killing people, etc. - we've seen it all, haven't we, Donuel?), not just mask advocacy. As I've said 'til I'm blue in the face, the precautionary principle is a perfectly respectable position on which to predicate your attempts to persuade people to wear masks. But, in my view, you don't start imposing arbitrary laws on people unless you are certain beyond reasonable doubt of your position, and when it comes to masks that is not possible. Remember, we still live in democracies.