> Everyone is already under the imposition of public policy, right now.
To the extent that this is true, it is, IMO, mostly a bug, not a feature.
> the public policy imposed on us today is based on what we thought we knew back when it was put in place.
If you seriously believe the public policies we have today were all based on the best current knowledge at the time they were put in place, all I can say is that you have a most charming naivete.
> I hope we can agree that is an ideal to aspire to.
It's an ideal to aspire to, but only if the ideal includes a very strict standard on what level of knowledge justifies dictating a public policy at all.
snowwrestler has repeatedly made the point that you can't not have a public policy about something; you can only accept or change the status quo.
England has a public policy that people drive on the left. America has a public policy that people drive on the right. In a society that had no codified rule about which side of the road to drive on, where people just weave back and forth, the choice to not enforce a particular convention would also be a defacto public policy.
It seems to me that in general you should only need the preponderance of evidence to suggest that a public policy change will do more good than harm in order to adopt it; otherwise you're unnecessarily biasing yourself in favour of the status quo. This of course should be done with an appropriate risk-weighting decision theory (how you weigh a small chance of large negative utility against a large chance of small positive utility, etc).
> England has a public policy that people drive on the left. America has a public policy that people drive on the right.
Neither of these policies were imposed by government. They were conventions that naturally evolved without any top-level policy being dictated, because they are obvious ways of solving an obvious coordination problem about using roads, and only got codified in law after that natural process of evolution had taken place.
> in general you should only need the preponderance of evidence to suggest that a public policy change will do more good than harm in order to adopt it
Even this standard, while it is weaker than the one I have suggested for what is needed to dictate public policy to everyone, is still strong enough to exclude many public policies that are currently in force, or suggested.
If I start putting some stuff into your tapwater, or into the air around your house, and you feel convinced it's going to cause you harm, but I insist that it's perfectly safe, what standard of proof do you think you should have to put together to stop me from doing that? And what would need to constitute harm?
If it didn't hurt humans but just insects that you're fond of, or just the ozone layer that protects you from radiation, or just the climate that you've come to enjoy, what standard of proof is needed?
To the extent that this is true, it is, IMO, mostly a bug, not a feature.
> the public policy imposed on us today is based on what we thought we knew back when it was put in place.
If you seriously believe the public policies we have today were all based on the best current knowledge at the time they were put in place, all I can say is that you have a most charming naivete.