There has been some talk of making covid 19 vaccinnation compulsory. It may help to consider cases where careful behaviour is already compulsory.
A quick potter through the Internet suggests that use of seat belts in cars may have saved about 16 000 lives per year, and motorcyclists' helmets may have saved aroung 2000 per year. Some people would have used seat belts or helmets without compulsion, so the benefits of the legislation must be somewhat less than that. It appears that upwards of 10% of the British population are refusing vaccinnation. Although it is hard to estimate how many lives would be saved if the refusers were vaccinnated, a saving of around 10% of the covid 19 deaths so far recorded seems a reasonable first guess, suggesting that the case for compulsion is stronger than that for motor cyclists' helmets, but perhaps not quite as strong as for seat belts.
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