I just read The Strength of Weak Ties by Mark Granovetter (Am J Sociology 1973; 78:1360-80). It is a classic paper in sociology which I saw referenced in a business-oriented book discussing networking. The paper discusses interpersonal networks commenting that, “In one way or another, it is through these networks that small-scale interaction becomes translated into large-scale patterns . . . ” Granovetter points out that wide disseminate of information or innovation is unlikely if you focus on people with whom you are tightly connected (i.e. strong ties) because they probably already know one-another. Your strong-tie network is sort of a closed circuit with respect to information flow. For dissemination, people who serve as bridges to other networks are critical. Your relationship with such people is almost by definition a weak tie, because if they were a a strong tie they would be in your network. Thus, “. . . whatever is to be diffused can reach a larger number of people, and traverse greater social distance, . . . , when passed through weak ties rather than strong.” (p. 1366).
Weak ties are important for learning about new opportunities. Granovetter asked people who recently got new job through contacts how often they saw the contact at the time the information about the opportunity was passed to them. Only 17% heard this information from someone they interacted with at least twice per week; 28% heard this information from someone they interacted with at most once a year.
Over the course of my mentoring of early career scientists, I’ve increasingly emphasized the importance of networking, which I now understand as way to build weak ties. This is most easily done through work, participation in scientific societies and scientific meetings. Casual interactions are a great way to learn about opportunities such as jobs, grants and research projects. They are also a way of introducing the world to your interests and goals which may lead to additional opportunities in unexpected ways.
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