It might be interesting to recast Norman's conceptions of "knowledge in
the head vs. knowledge in the world" . The dichotomy is problematic.
Whereas I think Norman's ideas have been very useful to help the design
process I do not think they can withstand an analysis based on the
summary of the cultural-historical conception of the basic structure if
human activity given on page 9 of "Distributed Cognition" .
Martin.