Indra's net
Indra's net (also called Indra's jewels or Indra's pearls, Sanskrit Indrajāla) is a metaphor used to illustrate the concepts of Śūnyatā (emptiness), pratītyasamutpāda (dependent origination), and interpenetration in Buddhist philosophy.
The metaphor's earliest known reference is found in the Atharva Veda. It was developed by the Mahayana school in the 3rd century Avatamsaka Sutra and later by the Huayan school between the 6th and 8th centuries.