The rates reach 45% in Australia, and I suspect much of Europe is something similar. France was proposing 75% recently. It's true that these are marginal rates.

The rates reach 45% in Australia, and I suspect much of Europe is something similar. France was proposing 75% recently. It's true that these are marginal rates. But consider how much taxes would need to rise to pay for the basic income. Let's say 50% of people who are eligible for basic income actually work. Then you'd need to collect two times the basic income from each of those people, on average. Surely this would push marginal, and probably overall, tax rates over 50%. Tax rates this high are only going to encourage even more people to give up working. I suspect such an economy would simply collapse. It's possible that invention of Star Trek replicators would change things. If people could have all material things they wanted with minimal effort, then I imagine that the remaining work could move to a volunteer model.