Summary: A short book that felt longer than it was because it felt like a book report.
I like the idea of introduction books. Short books that are able to give an introduction to an idea or a person can be very helpful, but also very hard to write.
I have read a number both the Armchair Theologian books and the Oxford Very Short Introduction Series. They are a very mixed bag. The best of the Armchair Theologian series that I have read is the book on Aquinas by Timothy Mark Renick.
This book by Scott Paeth is definitely on the weaker side. I am still glad I read it because I did not know much about the biography or context of the Niebuhr brothers. Their context and history is important to their writing. I have read at least one book by each of the brothers. So I was not coming into the book blind.