Long before we start exploring alternatives, we also begin to disconnect socially and psychologically. A slow and gradual shift in reference groups—relevant points of comparison—starts to take place. June, for example, began to identify with the values, norms, attitudes, and expectations of people working in the business world and began building relationships with people outside academia. The nuns in the “becoming an ex” study likewise began to cultivate relationships with laymen and -women, using these contacts to evaluate how they might adjust to life outside the convent.

In the mid-1970s, a Harvard sociologist named Mark Granovetter published what became the landmark study of how people get jobs. What he found and others have confirmed, is still true today: Most people find their jobs through personal connections. What surprised Granovetter—and hence the name of his famous “strength of weak ties” study—was that those personal contacts were neither friends, family, nor close work associates.

What makes a contact useful for a job change, argued Granovetter, is neither the closeness of our relationship with them nor the power of his or her position. It is the likelihood that the person knows different people than we do and, therefore, bumps into different information. The acquaintances, neighbors, and coworkers who operate in the same spheres as we do can rarely tell us something we don’t already know because they hear about the same things we do. Of course, having an Ivy League, Oxbridge, or Grande École connection can dramatically improve one’s prospects for moving into certain closed circles.

Our close contacts don’t just blind us, they also bind us to our outdated identities. Reinventing involves trying on and testing a variety of possible selves. But our long-standing social networks may resist those identity experiments. Remember Gary McCarthy’s chagrin when he learned, three years out of college, that his family had already pegged him as a “finance person”? Without meaning to, friends and family pigeonhole us. Worse, they fear our changing.

The sociologist Mark Granovetter has done important research showing the crucial significance of these casual ties. People we know only peripherally, Granovetter has argued, create important bridges to new social networks.