> If you have the same people buying and selling stuff faster, they may still retain the same wealth but the economy will grow even further.
At the expense of future growth. All of the money borrowed must eventually be paid back, which reduces growth by reducing that same money supply (increasing taxes to pay for it reduces the money supply similarly). It only makes sense to borrow when the future rate of return is greater than the interest rate of the debt, i.e. it'll take more than 8 years to see any return on investment from UBI.
At the expense of future growth. All of the money borrowed must eventually be paid back, which reduces growth by reducing that same money supply (increasing taxes to pay for it reduces the money supply similarly). It only makes sense to borrow when the future rate of return is greater than the interest rate of the debt, i.e. it'll take more than 8 years to see any return on investment from UBI.