Opinion dynamics with memory: how a society is shaped by its own past

Abstract: 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.