The Tipping Point: How Little Things Can - By Gladwell, Malcolm Page 0,64

the kind of emotionally sophisticated, character driven, multi layered novel that invites reflection and discussion, and book groups were flocking to it. The groups of women who were coming to Wells’s readings were members of reading groups, and they were buying extra copies not just for family and friends but for other members of their group. And because Ya Ya was being talked about and read in groups, the book itself became that much stickier. It’s easier to remember and appreciate something, after all, if you discuss it for two hours with your best friends. It becomes a social experience, an object of conversation. Ya Ya’s roots in book group culture tipped it into a larger word of mouth epidemic.

Wells says that at the end of readings, during the question and answer session, women in the audience would tell her, “We’ve been in a book group for two years, and then we read your book and something else happened. It started to drop down to a level of sharing that was more like friendship. They told me that they had started going to the beach together, or having parties at each other’s houses.” Women began forming Ya Ya Sisterhood groups of their own, in imitation of the group described in the book, and bringing Wells pictures of their group for her to sign. Wesley’s Methodism spread like wildfire through England and America because Wesley was shuttling back and forth among hundreds and hundreds of groups, and each group was then taking his message and making it even stickier. The word about Ya Ya was spreading in the same way, from reading group to reading group, from Ya Ya group to Ya Ya group and from one of Wells’s readings to another, because for over a year she stopped everything else and toured the country nonstop.

The lesson of Ya Ya and John Wesley is that small, close knit groups have the power to magnify the epidemic potential of a message or idea. That conclusion, however, still leaves a number of critical questions unanswered. The word group, for instance, is a term used to describe everything from a basketball team to the Teamsters Union, from two couples on a holiday to the Republican Party. If we are interested in starting an epidemic—in reaching a Tipping Point—what are the most effective kinds of groups? Is there a simple rule of thumb that distinguishes a group with real social authority from a group with little power at all? As it turns out, there is. It’s called the Rule of 150, and it is a fascinating example of the strange and unexpected ways in which context affects the course of social epidemics.

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There is a concept in cognitive psychology called the channel capacity, which refers to the amount of space in our brain for certain kinds of information. Suppose, for example, that I played you a number of different musical tones, at random, and asked you to identify each one with a number. If I played you a really low tone, you would call it one, and if I played you a medium tone you would call it two, and a high tone you would call three. The purpose of the test is to find out how long you can continue to distinguish among different tones. People with perfect pitch, of course, can play this game forever. You can play them dozens of tones, and they’ll be able to distinguish between all of them. But for the majority of us, this game is much harder. Most people can divide tones into only about six different categories before they begin to make mistakes and start lumping different tones in the same category. This is a remarkably consistent finding. If, for example, I played you five very high pitched tones, you’d be able to tell them apart. And if I played you five very low pitched tones, you’d be able to tell them apart. You’d think, then, that if I combined those high and low tones and played them for you all at once, you’d be able to divide them into ten categories. But you won’t be able to. Chances are you’ll still be stuck at about six categories.

This natural limit shows up again and again in simple tests. If I make you drink twenty glasses of iced tea, each with a different amount of sugar in it, and ask you to sort them into categories according to sweetness, you’ll only be able to divide them into six