The focus on rent is a good legacy of George's theory. However, I was quickly disappointed by the book that was linked. George was doing well critiquing previous economic theory that had separate theories of wages, rent, and profit. He showed instead that it must be that production = wages + rent + interest, as a formula that relates them and can be rearranged. Then in the next chapter, 12, he falls into a sort of absurdity about the nature of interest, where he claims interest exists because of natural increase, such as of bees or ageing wine, and wouldn't exist otherwise.

That's not an advanced enough theory of why there's interest on capital and the rate of it. It doesn't even seem quite sane, in comparison with the example of reasoning that he was setting and teaching up to that point. There should be some school of economics that promotes a George-like view of rent, but that isn't embarrassing when it comes to explaining capital and interest.