In Beyond Design Ethnography, Lysianne Léchot Hirt writes about “Users in Design” and includes a interesting analysis of how the discipline of design has evolved from a focus on the object, to the user, to the actor. This is commonly referred to as the Bremmen Scale after where a symposium to place and this model was first proposed by Alain Findeli and Rabah Bousbaci. Léchot Hirt states that:
This evolution clearly shows a progressive shift from the aesthetic understandings and analysis of design (from the Renaissance to the early Modern movement) to a methodological-technical one (around the 1950s) to a contemporary model centred on psychological and social values (from 1990s onwards). Léchot Hirt, L. (2014)
The notion that contemporary design is centred on psychological and social values links with the theory of design having agency.
It is important to note that it is acknowledged that even though the discipline is continuously evolving, the evolution of a new focus does not remove the older ideas. They remain valid and important, but can be seen as enabling a new way of thinking.