In reply to JLS:
Gradually over a few decades change the focus of the tax system from earned income to wealth and consumption of natural resources.
Start from the principle that everyone owns the land and natural resources such as wind, water, oil and the state collects payment for the use of the shared resources and pollution caused and distributes it to the population. The more land you use and the more demand there is for that land the more tax you pay.
Get rid of all tax breaks for financial services and investment. Tax unearned income harder than earned income and make it near impossible to pass large amounts of wealth down through families or increase wealth by passively sitting on investments.
Scrap the whole concept of pension and benefits and have a universal basic income.
The situation we are in now is ridiculous. We have more technology than ever before and our population is relatively stable. There's no physical reason why everyone can't have a good standard of living, what we have is a failure of the economic system to respond and develop along with technology. Technology is not slowing down, AI will make human labour less and less necessary and genetic engineering will lengthen lifespans. We need to give the idea of unearned wealth from investments and property to get a model which works under the new circumstances.