Hostile worlds is sociologist Viviana Zelizer's term for the view that the market must be kept separate from intimate, sacred and otherwise important spheres if they are to retain their value and importance. As she says, it is the assumption "that the entry of instrumental means such as monetization and cost accounting into the worlds of caring, friendship, sexuality, and parent-child relations depletes them of their richness, hence that zones of intimacy only thrive if people erect effective barriers around them."
This is contrasted with the "Nothing But" view, where we do not have separated spheres of money vs. intimate relations, but there is nothing but the market (or culture, or politics).
This theory has been productively used to study intimate relations, as in Zelizer's other work, but also to examine care relationships, art and other areas. For example, Olav Velthuis used this to understand the views of contemporary artists and their hostility to investment interests, while Coslor found this to be a prevalent view for collectors and art lovers, though not necessarily all gallerists.