In social networks, group boundaries promote the spread of ideas, study finds
phys.org
phys.org
Loosening these tight group boundaries means that people's next-door neighbors may have different jobs or levels of education, but they may still have similar politics or recreational activities. These similarities allow people in different social groups to encourage the adoption of a new complex idea, take neighborhood recycling as an example, which can then spread to other neighborhoods and social groups.
But when group boundaries are eliminated entirely, people have almost nothing in common with their neighbors and therefore very little influence over one another, making it impossible to spread complex ideas.
The most effective networks have high levels of 'inner-trust' to generate ideas between participants, and cross-pollinating trust' to share ideas between networks.
One can make good arguments in favour of trade barriers as well (related also: "globalization", https://en.wikipedia.org/wiki/Criticisms_of_globalization)
For example, Milgram (1969) found in his famous letter-delivery experiment that the strongest predictor of success when sending a letter across ethnic lines was whether the first jump between ethnic groups was a "strong" or "weak" link -- weak links were significantly more likely to end in a successful transmission. This is almost certainly because ethnicity tends to be an accidental (due to uncontrollable historical factors) signal of socioeconomic group; weak ties are more likely to be across socioeconomic boundaries.
There may be more to the article than the press release indicates; Centola is a former MIT professor with a background in computational modeling, so I assume he brings something new to the table here.
I'm not sure if he's being sarcastic. I thought that this was the explicit original purpose of the internet.
"Counterintuitively, he finds that breaking down group boundaries to increase the spread of knowledge across populations may ultimately result in less-effective knowledge sharing. Instead, his research shows that best practices and complex ideas are more readily integrated across populations if some degree of group boundaries is preserved. "
Every kind of social group has its pros and cons.