ABSTRACT
The emphasis on finding and describing 'knowledge structures' that are somewhere 'inside' the individual encourages us to overlook the fact that human cognition is always situated in a complex sociocultural world and cannot be unaffected by it. (Hutchins, 1995, p. xiii)
In the previous chapter, Dekker and Ltitzhoft introduced the dichotomy of mind and matter that is typically suggested by discussions of Situation Awareness (SA). In some respects this chapter provides another tactic for escaping this dichotomy to address the issue of 'what matters.' That is, we propose an approach to situations that reflects the relations associated with satisfying functional goals in work ecologies. This approach is based on Rasmussen's (1986) Abstraction Hierarchy and is consistent with Simon's concept of problem space and Gibson's concept of ecology. Note that the concepts of problem space and ecology do not reflect environments independent of observers. Rather, they describe situation constraints that are intimately related to observers in terms of intentions and intrinsic constraints on perception and action. Similarly, these constraints reflect the environments in terms of consequences and external constraints on perception and action. The abstraction hierarchy describes the confluence of internal and external constraints as a nested hierarchy of means-ends relations.
