Social Contagion and the Foundations of a Good Society | Nicholas Christakis, MD, PhD, MPH

One of the most fascinating concepts in human health is the idea of social contagion, meaning that emotions, behaviors, and health outcomes can spread through social networks, much like infectious diseases. Examples in the medical literature abound: if a person becomes obese, their friends have a significantly higher chance of becoming obese — even their friends of friends have increased odds of becoming obese. Similarly, someone who quit smoking is likely to create a ripple effect through th...