  We expect that democracy enables us to utilize collective intelligence such
that our collective decisions build and enhance social welfare, and such that
we accept their distributive and normative consequences. Collective decisions
are produced by voting procedures which aggregate individual preferences and
judgments. Before and after, individual preferences and judgments change as
their underlying attitudes, values, and opinions change through discussion and
deliberation. In large groups, these dynamics naturally go beyond the scope of
the individual and consequently might show unexpected self-driven macroscopic
systems dynamics following socio-physical laws. On the other hand, aggregated
information and preferences as communicated through media, polls, political
parties, or interest groups, also play a large role in the individual opinion
formation process. Further on, actors are also capable of strategic opinion
formation in the light of a pending referendum, election or other collective
decision. Opinion dynamics and collective decision should thus not only be
tackled by social choice, game theory, political and social psychology, but
also from a systems dynamics and sociophysics perspective.
