I have found Mario Bunge´s work of greatest interest to Philosophy of
design. His Treatise on Basic Philosophy is relevant for both Science
and Technology. It covers, semantics, ontology, epistemology and ethics.
Sadly it is rather expensive to buy. Technology is in my view one way of
framing Design theory. Concerning Epistemology, I have found Bunge´s
work on the concept of Problem very interesting since I think it has
relevance to any epistemic field. He also deals with this in his
"Philosophy of Science" vol. 1. Transaction Publishers ISBN:
Other authors of major importance are Donald Schön with the Reflective
Practitioner and Chris Argyris with Action Science.
None of these deal explicitly with issues of style, fashion or rule
based behaviour which I understand are also necessary aspects of a
design theory. Jerker Lundequist in his thesis Norm and Model (1982),
KTH, has pointed at Georg Henrik von Wright´s (1963) Norm and Action,
London: Routledge & Kegan Paul, in this respect.