The great Japanese Zen master Hakuin exclaimed, "How priceless is the merit gained through the step-by-step practice of the Five Ranks of Master Tozan!" Hakuin here refers to a teaching created by the Chinese Buddhist master Dongshan, known in Japanese as Zen Master Tozan, which is honored and studied in both Soto and Rinzai schools of Zen and is a gem of the classical Zen tradition. The ranks serve as guides to a radical exploration of the experience of relative and absolute reality, the interpenetrating "Two Truths" of Mahayana Buddhism.

In The Five Ranks of Zen, American Zen teacher Shishin Wick offers an accessible entry point to each of the ranks, which Tozan created in two formulations: the first and better-known is the Five Ranks of the Relative and the Absolute; while the second set, called the Sequence of Merit, is an abbreviated form of the Ten Oxherding Pictures, a traditional formulation of the Zen spiritual journey. Wick presents multiple translations and offers commentary on the ranks' titles and on Tozan's renowned verses, as well as offering guidance on these teachings' application in contemporary life and Zen practice. He emphasizes that, to truly plumb the depths of Tozan's teachings, you must treat these teachings as Zen koans and make a thorough investigation using your entire body.