The author demonstrates in this book how ultimate and conventional reality coexist. It is a key to understanding the essential concepts of Buddhism. The so-called "emptiness" or Shunyata can only be grasped if one can accurately trace how things in the "real world" appear to us. This subtle point of Buddhist philosophy is often described entirely incorrectly or in an unclear, incomprehensible manner. This text is like opening a door to a clear understanding of emptiness.