Multilevel Systems and Policy Multilevel Systems and Policy

A formal theory of multilevel systems is needed for modelling the outcomes of policy. The dynamics of social systems are coupled between levels and models that do not reflect this are incomplete and a poor basis for policymaking. The structures developed here are necessary for the new kinds of models and computer simulations needed to support policy makers as they tackle the problems of an increasingly connected multilevel world. Almost all social systems have many levels of organisation, from micro to macro levels, and multilevel structure is fundamental to their dynamics. Part-whole structures play a major role in multilevel systems, where intermediate wholes may themselves be parts in higher level structures. Taxonomic aggregation plays another major role in multilevel systems, but is very different to part-whole aggregation. Generally part-whole and taxonomic aggregation are interleaved. Both space and time have natural multilevel structure relevant to social organisation. Multilevel structure can be relational or numerical. Generally relations determine organisational structure, with patterns of numbers defined on it. These numbers aggregate and disaggregate with the multilevel part-whole and taxonomic structures. In this chapter the ideas are developed descriptively in the first instance in order to be accessible to everyone. The second part uses a more formal approach that enables the fundamental concepts to be developed with greater precision.