Can you expand on that? Does that include capital investment if one meets the loose "materially participated" stipulation?

"The prime candidates are the land value tax and carbon tax."

This doesn't seem like a good idea. A carbon tax is transactional, so it could be avoided. Maybe good for policy implementation but not good for revenue. Land tax seems very similar to property tax already. We are seeing pushes in many states to eliminate it due to the high burden on lower income families and the elderly. For example, you may be taxing them on "wealth" that doesn't exist. This places the government in a position to take assets someone already owns. It's also mostly regressive as property tax is now. If you tax the inflow of money, then you know there is money that can be paid and can even be collected before the person ever receives it.