There are certainly tough questions in design research, but I have never thought of this as one of them.

"The Psychology of Everyday Things" by Donald Norman, published in 1988, was republished in 1998 as "The Design of Everyday Things" with a new preface. I am pretty convinced that changing the title was a simple market decision: "Design" was deemed to sell better than "psychology" at the turn of the century. I would not take that as grounds for any serious discussion on the interchangability of psychology and design, and I doubt that Norman would either.

Regards,

Jonas Löwgren

PS. If I just made the classic non-native-speaker-mistake of not spotting a joke or a piece of irony, I apologize for adding noise to the list. To me, it looked like your last paragraph was meant to be a sincere reflection.