Mandala of the Diamond World (Kongokai mandara), one of a pair of Mandalas of the Two Worlds (Ryokai mandara)

What is a mandala? The examples displayed here might be described as "cosmograms"—pictorial diagrams of the cosmological path to enlightenment as described in Buddhist scriptures. Mandalas are closely associated with the Shingon and Tendai schools of Japanese Esoteric Buddhism—a form of Buddhism that is related to the Tantric Buddhism of the Himalayan region. The mandalas shown here were carefully copied after the oldest surviving color mandalas in Japan, a pair dating to the 800s that was kept in Toji temple in Kyoto. Those in turn were copied from earlier Chinese models.
How were mandalas used in Buddhist practice? Traditionally, mandalas have been described as visualization aids for meditation by monks in training. The two paintings reveal the process of human enlightenment, respectively, through innate reason (ri) and knowledge (chi). Some scholars argue, however, that they have been less important as meditation aids than as ritual objects within particular religious traditions.
These mandalas were donated to the museum by Pulitzer-Prize winning writer Gary Snyder (American, b. 1930), who lived in a Zen monastery in Japan for many years and studied various forms of Buddhism, including Shingon esotericism. He acquired these mandalas in 1967.