Principles of Economics by Saifedean Ammous is a very solid book about Austrian economics. The book that established Austrian economics was a book with the same title written in 1870 by Carl Menger. This new book written in 2023 can be seen as an update on all the economic topics in the Austrian perspective looking at everything written by all the important authors of the Austrian school including Ludwig von Mises, Friedrich A. Hayek, Murray Rothbard, Hans-Hermann Hoppe etc. In certain areas Saifedean advances and clarifies the Austrian thought as for instance in terms of energy, intellectual property etc. In the latter there was quite some confusion in the Austrian and Libertarian circles and I guess he nicely clarifies that point, there is no such thing.