Progress and Poverty
This was a book written in 1879, by political economist Henry George:
https://en.wikipedia.org/wiki/Progress_and_Poverty
The basic idea is that as technology makes cities richer, many people still remain poor, because their extra income flows to the people who own the land in any given location. Land is inherently a scarce resource, and so whoever owns it can collect arbitrarily high rents from whoever is using it as the economy grows, while contributing nothing productive to the rest of society. The solution is a "single tax" - replacing all other taxes with a tax on the value of land (like property tax, but just on the land itself, not on buildings and so on). The land value tax is the most efficient tax, because it collects revenue without disincentivizing anything, and without penalizing anyone except landowners. There's a very detailed summary of the book itself here:
https://astralcodexten.substack.com/p/your-book-review-progress-and-poverty
However, IMO, what is most interesting is the book's trajectory. In the 1890s, Progress and Poverty was insanely popular, reportedly the best-selling book in the United States after the Bible. Since then, it's been almost completely forgotten; Georgist groups today are mainly small Internet communities of fanatical nerds. Nothing has fundamentally changed, as far as I know. Georgism still seems like a great idea with some moderate implementation challenges, just like it was seven generations ago. But it seemed important then, and now it doesn't, and I'm not quite sure why.