My kind of book! One of the hardest thing to do is see errors in thinking. Overall this book gives a great discussion about forms of thinking namely art, religion, science, history, and philosophy, what are the inherent errors, and further, how each has its place in the development of a human, or humanity, and how one form of thinking can lead to the other in a kind of cycle.
Also there was a great insight into the metaphorical nature of religious thinking completely missed by both the religious and the rationalists that oppose them.
In the end the goal is that the mind should know itself.
Quote near end:
In an immediate and direct way, the mind can never know itself it can only know itself through the mediation of an external world, know that what it sees in the external world is its own reflection.
Another quote:
We did not assume that any one form of experience could be accepted as already, in its main lines, wholly free from error. Led by this principle, we found that the real world was implied, but not asserted, in art; asserted, but not thought out, in religion; thought out, but only subject to fictitious assumptions, in science; and therefore in all these we found an ostensible object—the work of art, God, the material universe—which was confessedly a figment and not the real object. The real object is the mind itself, as we now know.
This book will excercise your mind!
Note 1: I was happy to have read "The Idea of History" by R. G. Collingwood first, even though it was published later. It gave the background for talking about history, and thinking, only briefly touched upon in this book.
Note 2: there are errors in the Kindle version of the book from the OCR scanning that have not been caught by the editing. However it is still very readable