> UBI proponents should be cognizant of stagflation.
Everyone should be. =)
> In reality the Phillips curve was too simple.
Yes. The Phillips curve relationship between inflation and unemployment only holds under certain conditions. Policymakers thought they could stimulate the economy by causing inflation, but this kind of thing isn't going to work if the underlying problem with your economy is that you have less access to resources (in this case, oil).
So the policymakers made a mistake in the 1970's. And, as you say, the expectations of inflation led to institutional inflation, which is basically just inflation that reinforces itself out of habit.
Small amounts of inflation can be okay because they help the economy more evenly absorb adverse conditions. For example, instead of firing a bunch of your workers, inflation allows you instead to choose not to give people raises. But there's a limit to how much benefit you can get out of inflation.
> UBI could lead to stagflation because the income allotments and any increases would be according to some formula known ahead of time. This means that producers could anticipate demand and simply raise prices to soak up any income increases.
Hmm. I'm not sure this is right. UBI or not, you need to keep inflation in check. But there's a lot more to inflation than just the amount of money in circulation.
In order to keep prices stable, the amount of spending in the economy must stay aligned with the amount of actual stuff being traded. Generally speaking, monetary policy keeps prices stable. If there otherwise would be deflation, monetary policy incentivizes borrowing (lowers interest rates) to increase the amount of spending in the economy. If there would otherwise be inflation, monetary policy disincentivizes borrowing (raises interest rates).
UBI, on its own, won't cause inflation, let alone stagflation. In fact, it can lessen the need for monetary policy to encourage borrowing in the private economy. Through the monetary policy response it induces, basic income can take some of the fuel away from the speculative bubbles that tend to destabilize the economy every so often.
However, Circles hasn't described how they plan to implement monetary policy. Without solving the problem of price stability, they won't have much of a currency, let alone a basic income. A flat increase in the amount of the basic income isn't going to cut it. Monetary policy must be able to respond to various economic conditions.
It's probably a mistake not to keep your monetary policy separate from your basic income.