In the nineteenth century, stiff crinoline petticoats puffed out skirts so far that cheap materials often brushed against open flames and caught fire. This arbitrary convention of dress caused three thousand women to be burned alive. Meanwhile, men wore wool suits both flameproof and close to the body.

We have no record of cultureless human societies.

Living in proximity to sugar factories, the Galician Jews of Ukraine and southeastern Poland came to prefer sweeter foods. Meanwhile, Litvak Jews, without access to beet sugar, ate saltier dishes. Despite their having a common language and genetic origin, the culinary distinctions between them became conventional, habitual, and imbued with meanings and norms. Even today Galician descendants still prefer sweet gefilte fish, while American-born Litvak grandmothers complain about those Galitzianers who put sugar in everything.

In the words of anthropologist Mary Douglas, imitation creates “bridges” to compatriots, while distinction raises “fences” to keep out rivals. But where differences occur, every meaningful act of imitation also functions as distinction. Every bridge serves as a fence.