What does the term molecular cement that links individuals in groups by Robert Nisbet refer to?

The term "molecular cement" was not coined by Robert Nisbet. It is more likely you are thinking of "social cement", a concept used by Nisbet in his work, particularly in his book *The Quest for Community*.

In his book, Nisbet argues that "social cement" refers to the shared values, beliefs, and institutions that bind individuals together in a society. These elements act as a glue, holding individuals together and creating a sense of community.

Here's a breakdown of what Nisbet might have meant by this:

* Shared Values: Common morals, principles, and beliefs that people within a group hold dear.

* Shared Beliefs: Agreement on foundational truths and assumptions about the world and society.

* Shared Institutions: Organizations and structures that serve a common purpose, such as family, religion, or government.

Nisbet argued that the decline of traditional social cement in modern society, due to factors like industrialization and urbanization, has led to a sense of atomization and social fragmentation. He believed that the loss of these shared elements weakens social bonds and creates a sense of alienation and disconnection.

In short, "social cement" according to Nisbet, refers to the shared cultural and institutional elements that bring individuals together and contribute to a sense of community and belonging.