[Bizarro]

I don't see how markets are supposed to solve that when we allow countries with slaves to participate on the markets.

The idea that the small number of countries with however many number of slaves distorts the markets is ludicrous.

[SolarNet]

It's not that it distorts the market, but it's one reason why the assumption that markets some how solve the principle agent problem in the first place is wrong.

My personal argument is that I don't believe markets solve either the principle agent problem or the economic calculation problem, and so to require them of other systems is hypocritical. But even if markets somehow do, then Turing completeness would strongly imply that there are other economic systems that also have those properties. Otherwise magic (which this paper is evidence against).