Friendship cannot exist “between the well-fed, prosperous / and the lean and down-and-out in the world,” states the Panchatantra, a collection of Indian animal fables from around the third century bc. In one story, when a crow tries to befriend a mole after witnessing his impressive skill in escaping from hunters’ traps, the mole exclaims, “You are the eater; I am the food. What kind of friendship can exist between us?”

A fourteenth-century-bc peace treaty recorded on a cuneiform tablet contains an invocation to Mithra, the Indo-Iranian god of the sun as well as of oaths and mutual obligation. In the Roman Empire, Mithras was honored as the god of loyalty to the emperor, while in Indian Vedic texts, he represents friendship and benevolence and, along with the god Varuna, is entrusted with the maintenance of the gods’ essence.