I first read Gary Zukav when I was in the 8th grade, his book on the dual nature of particles, The Dancing Wu Li Masters. And although he has written a few books on such a topic of spirituality, the Seat of the Soul was the first that was a refreshing authorship on the subject.
The book is definitely not an original on the topic. It is neither a compilation of ancient texts on non-duality and their meanings, like so many authors have done (and are still doing with the sole purpose of publishing something!). The book is rather a heartfelt understanding of awareness of one’s self, leading to a better understanding of mindfulness, empathy and a general benevolence towards humanity & life in general.
This book will not influence or change your understanding of either the spirit or the cause of existence but will impress upon you the need for self reflection. It will not shower you with more abstract concepts of philosophy but will simply expect you to look within yourself & find a deeper meaning of what we know as the soul. It may in fact ask you to look at things from your heart rather than just your head that could lead to a life that is simpler and more rewarding.