The Tipping Point is a book by Malcolm Gladwell that talks about social epidemics.
This is the idea that people who are not in your normal social circle can introduce to new perspectives.
Why is this? Granovetter argues that it is because when it comes to finding out about new jobs—or, for that matter, new information, or new ideas—“weak ties” are always more important than strong ties. Your friends, after all, occupy the same world that you do. They might work with you, or live near you, and go to the same churches, schools, or parties. How much, then, would they know that you wouldn’t know? Your acquaintances, on the other hand, by definition occupy a very different world than you. They are much more likely to know something that you don’t.
This reminds me of the immense value of conferences and “hallway tracks”.
Three Rules of the Tipping Point
The three rules of the Tipping Point—the Law of the Few, the Stickiness Factor, the Power of Context
These rules allow us to try to study and influence if/when a tipping point may occur.