Does the spiritual tradition of the East offer a viable alternative to the perceived moral and intellectual failures of Western rationalism? Arthur Koestler, a prominent intellectual and former journalist, documents his travels through India and Japan to investigate the intersection of ancient mysticism and modern technological advancement. He argues that the spiritual practices of these nations are often misunderstood by Western observers and frequently fail to provide the practical solutions required for contemporary societal challenges.

This work is regarded as a provocative and highly critical assessment of Eastern philosophies, reflecting the author's deep-seated skepticism toward mysticism. The text serves as a dense, polemical account that challenges the romanticized view of Asian spirituality prevalent in the mid-twentieth century.