In this little jewel of a book, based on the Bhagavad-gita, Srila Prabhupada explains that the king of knowledge is knowledge of God, his creation, and ourselves -- and the relationships between these. He explains that the way to attain this knowledge is through bhakti-yoga, devotional service to the Lord, beginning with the chanting of the maha-mantra, Hare Krsna, Hare Krsna, Krsna Krsna, Hare Hare/ Hare Rama, Hare Rama, Rama Rama, Hare Hare.