I just finished reading Malcom Gladwell’s wonderful book – The Tipping Point. The book talks about how and why, word-of-mouth epidemics, spread. There are lot of interesting studies and data points, related to human behavior, referred to in the book. I wonder why business schools don’t teach this subject in more detail. This book is absolutely essential reading for any web 2.0 startup.

At its core, the book makes a very interesting and persuasive case for the inherent social and context dependent nature of human beings. One piece, I really found fascinating relates to the Rule of 150, which talks about the size of effective groups. For those of you who haven’t read the book, the Rule of 150 states that the size of an effective social network is limited to 150 members. It seems that the human mind is unable to maintain effective relationships with members in groups larger than 150 people. The interesting thing seems to be that if the number of people in a group increases beyond 150, the deterioration in group effectiveness is not gradual but sudden. Malcom Gladwell quotes S.l. Washburn for the rationale:

Most of human evolution took place before the advent of agriculture when men lived in small groups, on a face to face basis. As a result human biology has evolved as an adaptive mechanism to conditions that have largely ceased to exist. Man evolved to feel strongly about few people, short distances and relatively brief intervals of time; and these are still the dimensions of life that are important to him.

This is very interesting… I wonder how the rule of 150 applies to online communities. Does it mean, on-line communities, that free participants from the limitations of geography, are somehow contrary to inherent human nature? How can one apply the rule of 150 to on-line communities? My guess is that the rule of 150 very much applies to on-line communities. Still, there is an interesting tension between the technology that makes it really easy to communicate with a wider set of people, and the waning effectiveness of that communication, as one reaches a wider audience. Applying this concept to blogosphere, maybe what a blogger should do, is give up the ambition of greater reach in favor of improved richness with a few people.

Another important point in the book relates to the power of the context. Malcom Gladwell uses a number of interesting studies and examples to make a strong case that human behavior is dependent on context. This means that instead of individual behavior being predestined based on character, a change in context can make people behave differently. So, a change in context, can make can make a docile individual, violent, a non-smoker, smoke, or an angry person, commit suicide etc.

It follows, that any technology that can provide context and identity on individuals, has the potential to dramatically change the participation levels in online communities.