[Suncho]

This is a great question. I would say that the "answer from economics" you describe is incorrect. There are some economists who think this way. And they have a term for it: The Quantity Theory of Money.

But the reality is that inflation isn't about the amount of money "in the economy." It's about the rate at which money is flowing through the economy. That flow is the level of spending. To keep prices stable, we have to keep spending balanced with production.

The reason why we can make this distinction is because money doesn't just perpetually circulate through the economy. It flows through the economy like a river from consumers to producers to the financial sector. It's true that money in the financial sector gets "reinvested," but in order for that money to support consumer spending, you have to be able to connect the dots and tell a story about what mechanism is getting money into the hands of consumers.

Basic income is a possible mechanism for that. If we want to, we can continue to use taxes or create jobs to force "existing" money is flowing back into the hands of consumers, but what's the point? Why not just hand them new money instead?

I've written a blog post about this.

http://www.greshm.org/blog/money-does-not-circulate/