Among the many common geometric shapes and designs in Tantric Buddhist art, the tetrahedron is one of the most unique. The basic triangular shape began as a simple two-dimensional form representing one of the four elements. The triangle was also used as either a single three-line drawing or overlaid with its duplicate to create a Star of David-like shape that represents visual magic formulas called yantra. These were intended to be two-dimensional regardless of whether they were drawn or visualized.
The tetrahedron is different. In Tantric Buddhism, it is both drawn and imagined as a three-dimensional structure. Although the tetrahedron is a four-sided shape, only three sides are closed in Tantric Buddhism. The pointed end is always directed downward, while the flat, open side faces upward. The symbolic meaning of the shape is emptiness, in which the three closed sides represent the three types of emptiness: wishless, signless, and emptiness itself. Insofar as the tetrahedron represents emptiness, it also stands for the true source of all tantric mandalas and deities.
The image of Tara burning suffering from the Twenty-one Taras ( suryagupta) depicts her carefully holding a blue tetrahedron with two hands. Held like a bowl and filled with a cleansing fire, the tetrahedron incinerates misery and suffering. This particular artist has embellished the basic iconography with orange licks of flames.
The Vajrabhairava Mandala shown here, which gives a side view of a palace within an outer mandala ring, provides a useful example of the tetrahedron and its uses. The palace, deities, and the entirety of the mandala arise out of the tetrahedron and the three types of emptiness. In this example, the outside of the tetrahedron is white in color and the inside red. The shape’s colors can vary depending on the specifics of the particular tantric source literature.
The last example shows the deity Vajrayogini standing within a double-tetrahedron. In literature, this specific configuration is sometimes even referred to as the “palace” at the center of the mandala. The open sides of the two upward-facing tetrahedrons are merged to create the familiar Star of David appearance, overlapping in such a way that their two downward points merge into a single point.
The tetrahedron shape is not just limited to art and visualization of elements, mandalas, and deities in Tantric Buddhism; it also plays a role in internal practices involving the body, breathing, and Buddhist yoga.
Vajrayogini (Detail: Tara Burning Suffering). Tibet. Sakya and Buddhist lineages. Ground mineral pigment on cotton. Private collection.