[theptip]

Milton Friedman covers this in detail in “Capitalism and Freedom” if you want the full Libertarin justification, but the short answer is

1) voluntary certification, or

2) market reputation, or

3) threat of enforcement of anti-fraud laws that are less specific than licensure requirements.

The general idea being that it is seldom a good thing to remove cheap options (eg forcing poor people to go bankrupt instead of letting them choose worse care), and licensure both sets a quality floor, and also artificially restricts supply.

I think for life-and-death things like medicine this idea breaks down a bit, but that’s the end of the spectrum and how it’s argued as far as I’ve seen.

[imtringued]

I wouldn't trust Milton Friedman's opinion when it comes to life and death. He loves busting supporting pillars without first considering how to migrate off of them. His economic "misadventures" in China resulted in protests at the Tiananmen Square and everyone knows how that ended.

[theptip]

I think trying to blame Friedman for the Tiananmen Square massacre is a bit of a stretch.