The main question addressed in the book is how should society develop beyond the post-modern critique of the modern. Freinacht suggests that the focus should turn to promoting the emotional and psychological development of human "dividuals." A "dividual" not being the modern stage individual or the post-modern social construct, but rather the individual within her social construct. Thus, only societies that have achieved a reasonable level of post-modern development will be able to offer this level of service to citizens of any level of "dividual" development. So, Freinacht often refers to the model of the Scandinavian countries as offering glimmer of where we all may be heading in the future (given that we aren't headed straight down the tubes.)
The book is also a guide to recognizing your own level of development by several different measures. Freinacht is not a huge promoter of the "woo", so he renders some rather mushy human qualities such as "wisdom" into more objectively useful forms. I don't want to spoil the fun of reading this book, and figuring out or contemplating your own levels of development, so I won't go into more detail about his model.
The metamodern tone is described as irony mixed with sincerity and this is also the tone adopted by Freinacht. I found the book to be both provocative and inspiring. A few illustrative bits:
Unintelligent people don't like theory. They don't understand that the word theory just means "seeing", and that without it you miss out on seeing vital aspects of reality. Don't be like that. Theoreticians built this world; the rest of y'all just live in it.
But most conflicts are avoided in everyday life because we tend to keep most everyday institutions related to shallow aspects of life. It is much easier to create and maintain social settings and institutions that revolve around lower depth: It takes considerably less sensitivity and skill to set up a manual labor team, a movie night, or a game of golf, than it does to set up a successful psychotherapeutic treatment, a genuine talk about the meaning of life, or a truly sublime shared spiritual experience.
What is lacking in our day and age is the ability for people to manage complex problems that require patience, knowledge, oversight, creativity, mutual trust and friendly co-operation across sectors, scientific disciplines, cultures and subcultures. In a phrase: the management of complexity. Or, with a term we shall get back to, we require a greater collective intelligence.