elective affinity
a feeling of sympathy, attraction, or connection to a particular person, thing, or idea. The term was originally used to refer to certain chemical processes but took on a new figurative sense after the publication in 1809 of The Elective Affinities, a novel by Johann Wolfgang von Goethe (1749–1832). It is often used to mean those preferences and common feelings that constitute a cultural or national identity or that distinguish groups and subgroups from one another.