Many ancient stories concern the rules of hospitality. Every culture has a framework for describing the duties of a householder toward a guest, especially a traveler or stranger in need, and the duties of the guest toward their host. Violation of those rules provide the starting point for epics and tragedies. Given the hazards of travel, one can easily understand how hospitality became a recurring theme in morality and mythology. The householder welcomes the stranger because they can easily imagine themselves with the needs of the stranger. Then stranger accepts what is given gracefully and returns what they can because they would want a guest to treat their house the same way.
Hospitality norms reflect the fundamental role of reciprocity as a moral value. Reciprocity builds trust between individuals. By serving another’s interest and being served in return, one demonstrates regard for the needs and interest of another. Establishing reciprocity provides the foundation for all agreements and organizations.
Simple regard for another’s needs demonstrates respect and allows us to recognize common wants and needs. Despite the wide diversity of individuals, humans share a common set of basic needs, food, shelter, companionship, and recognition. Practicing reciprocity teaches a person these needs and teaches them to recognize the other as commensurable with themselves. In the continuity of self and other, one finds humanity.