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Although there have been changes in cognition and systems theory, I wanted to bring up some stuff Rasmussen published in the 80s that was really elegant. I'll use 3 diagrams he published, covering the ideas of abstraction hierarchies and how people operate systems when troubleshooting them.

The first one is the abstraction hierarchy from Coping With Complexity (1981). This shows how requirements and design tends to go top-down based on goals that must be met by the system. However, signals of problems tend to go bottom-up, from a local issue showing up as disrupted functionality.

The 2nd one (same paper) shows aggregation, where a nuclear power plant can be described as a whole conceptual system (top), as functional sub-units with material elements (middle), or as granular units that get closer to the material world (bottom).

Rasmussen maps these as a space across two dimensions: abstraction (purpose to physical) and decomposition (whole-system to individual components). Each component can have a physical set of properties, but also a high level purpose it is connected to; so do aggregated portions of a system.

He then describes how workers do their work by skipping around abstraction layers, going up and down the hierarchies based on both purposes (high-level goals and functions) and reasons (bottom-up signals) but also across various aggregations (whole systems vs. components).

The cool thing though is that he then maps a problem-solving path as a line walking that conceptual path within a "conceptual reasoning space" of operators that is event-independent. Neelam Naikar (doi.org/10.1016/j.ap...) re-renders diagrams Rasmussen had made in a few publications in the mid 80s: