That's just the same fallacy. Why can you assume the thing the employee is producing won't have less price elasticity than the thing the employee buys with the income, but I can't?
> the rich have a higher marginal propensity for consumption
Your argument is that the rich have a much lower marginal propensity for consumption, enough to really matter. And that may even be true if you're talking about a matter of $2, which a poor person would almost certainly use to buy lunch or the like but would have no effect on a rich person's level of consumption. But if you give a poor person $20,000, now you have to ask whether they aren't going use it to attend college or start a business. It's an entirely different dynamic.
Also, if the money is raised using a consumption tax then it can inherently never come from someone making an investment regardless of their income level, which kind of destroys your entire argument, since it is based on where the money comes from as much as who gets it.
> Giffen goods are common
Nobody is even talking about Giffen goods, that's the demand side. And goods whose total cost is dominated by fixed costs are extremely common.
> scarcity isn't real
Scarcity is often not relevant. The market price of a computer or pharmaceuticals or recorded music is completely divorced from the cost of the scarce materials necessary to manufacture it. There is no realistic volume of DVDs that could be produced that would materially affect the market price of plastic.
> If that is the case then the usefulness of a BI will also constantly be in flux.
Whether and to what degree it causes inflation or deflation would constantly be in flux. That it might possibly cause a small amount of inflation is hardly a condemnation, and it is unlikely to cause a large amount of inflation for the reasons I've already mentioned -- its tendency to increase prices in some products is offset by its tendency to reduce prices in other products.
Reducing unemployment will increase demand but will also increase supply. So no.
It could be that members of the lower middle class are hungry for an opportunity to start a business and will us the money to invest rather than consume...There are many products for which this relationship is negative. Where there is no practical limit on the number of units suppliers can produce...
So if I'm understanding you right, BI will work because the rich have a higher marginal propensity for consumption, Giffen goods are common and scarcity isn't real? Ok.
It depends entirely on the contours of the economy at a specific time and place and is constantly in flux.
If that is the case then the usefulness of a BI will also constantly be in flux. I guess your opinions on the topic are also constantly in flux? If not, why not?