Many models have been proposed to explain opinion formation in groups of
individuals; most of these models study opinion propagation as the interaction
between nodes/agents in a social network. Opinion formation is a complex
process and a realistic model should also take into account the important
feedbacks that the opinions of the agents have on the structure of the social
networks and on the characteristics of the opinion dynamics. In this paper we
will show that associating to different agents different kinds of
interconnections and different interacting behaviours can lead to interesting
scenarios, like the coexistence of several opinion clusters, namely pluralism.
In our model agents have opinions uniformly and continuously distributed
between two extremes. The social network is formed through a social aggregation
mechanism including the segregation process of the extremists that results in
many real communities. We show how this process affects the opinion dynamics in
the whole society. In the opinion evolution we consider the different
predisposition of single individuals to interact and to exchange opinion with
each other; we associate to each individual a different tolerance threshold,
depending on its own opinion: extremists are less willing to interact with
individuals with strongly different opinions and to change significantly their
ideas. A general result is obtained: when there is no interaction restriction,
the opinion always converges to uniformity, but the same is happening whenever
a strong segregation process of the extremists occurs. Only when extremists are
forming clusters but these clusters keep interacting with the rest of the
society, the survival of a wide opinion range is guaranteed.Comment: 20 pages, 10 figure