  In order to understand the development of common orientation of opinions in
the modern world we propose a model of a society described as a large
collection of agents that exchange their expressed opinions under the influence
of their mutual interactions and external events. In particular we introduce an
interaction bias which creates a collective memory effect such that the society
is able to store and recall information coming from several external signals.
Our model shows how the inner structure of the society and its future reactions
can be shaped by its own history. We will provide an analytical explanation of
how this might occur and we will show the emergent similarity between the
reaction of a society modelled in this way and the Hopfield mechanism for
information retrieval.
