The book is divided into three parts- The Mind in Every Day Living, The Mind and the Dream World , and The Mind After Death. "Due to the immateriality of mind or consciousness and the unknown mechanism thereof, the terms such as consciousness, mind, thought, emotion and the like are not clearly defined, even in the 21st century," Choi writes. "To discover the mechanism and to define the terms clearly are my concerns in this book." He adds that one of his objectives is to prove continuity of consciousness after death.

The first five consciousnesses are our sense consciousnesses, Choi explains, while the sixth consciousness, called the Manovujnana, is generated by the sixth organ, referred to as the "organ of Mind" or "root of mind." What exactly that is, Choi continues, we do not know. "However, it is crystal clear that the sixth organ is not the brain. It must be a non-physical and immaterialistic organ which capable of reading something..."

Choi goes on to explain the seventh consciousness, called Manas. Unlike the first six consciousnesses, this one does not have an organ. It involves think, cogitation, and intellection. "The first six consciousnesses perceive and discriminate their corresponding objects, and trigger to think so as to give rise to the seventh consciousness, Manas, which is accumulated in the eighth consciousness, Alaya, as seeds of mind (cittas)," Choi continues, adding that all mental activities are stored in Alaya.