This book has been written by Dr. Bernardo Kastrup.
Carl Jung is a hugely important figure in the history of psychology, and in particular within the field of psychoanalysis in relation to the concept of the collective unconscious, Jungian archetypes, and more. Concerning metaphysics, In Civilization in Transition (Volume 10 in The Collected Works of C. G. Jung) Jung wrote:
“Our mania for rational explanations obviously has its roots in our fear of metaphysics, for the two were always hostile brothers. Hence, anything unexpected that approaches us from the dark realm is regarded either as coming from outside and, therefore, as real, or else as a hallucination and, therefore, not true. The idea that anything could be real or true which does not come from outside has hardly begun to dawn on contemporary man.”
Concerning Dr. Kastrup’s book, the publishers say:
“More than an insightful psychologist, Carl Gustav Jung was the twentieth century’s greatest articulator of the primacy of mind in nature, a view whose origins vanish behind the mists of time. Underlying Jung’s extraordinary body of work, and providing a foundation for it, there is a broad and sophisticated system of metaphysical thought. This system, however, is only implied in Jung’s writings, so as to shield his scientific persona from accusations of philosophical speculation. The present book scrutinizes Jung’s work to distil and reveal that extraordinary, hidden metaphysical treasure …”
You can find out more from here.