Yesterday in my class I was asked by a student if there are any major schools of thought when it comes to design, in particular, how to understand designing (that is as a human activity and process). I really liked the question. I did answer the best I could right there, but since it was not something I have really thought about, it was just a tentative answer. I said that there are at the moment three major schools of thought when it comes to designing.
The first school of thought is very close to what I teach in my class, it is based on a broad understanding of design as an activity that is defined by such thinkers as Schon, Rittel, Cross, Krippendorf, Nelson & Stolterman, etc. It is a school of thought that sees designing as an open, complex and highly non-linear process determined by the particular situation and governed by the designer's judgment.
The second school of thought seems to see designing as a process that is in need of more structure and explicit rationality, as a process that is in need of being 'formalized' and maybe even 'scientized'. Attempts to achieve this can be found in almost every design field and is quite common among design researchers who see as their task to improve designing by increasing its predictability usually by becoming less dependent on the designer's judgment.
The third school of thought is what is today commonly called 'design thinking'. It is mostly found in the business world and in academic fields that has no tradition of design. Design thinking is in many ways a highly simplified version of the first school of thought mentioned above (with some aspects of the second school). It has reduced designing to a simplistic process consisting of some phases with attached tools or techniques. Design thinking usually portrays designing as a process where the steps and phases and its iterative nature in combination with some very simple 'tools' is the core, while the designers judgment is not seen as crucial. Usually this school advocates for crash courses or workshops as a way of mastering designing. This school of thought has been highly successful in making designing popular in the business world and in academia. It has raised the awareness of design as its own tradition, however, in many cases by promising too much and delivering too little.
Ok, so this is the answer I gave the student in my class. I have not really thought more about it. It is obvious though, that these schools of thought only relate to a specific aspect of design, that of design as a process, as designing. But even so, I think it is something that would be really exciting to develop more. It would be a great help to all of us to are navigating the world of design theory. Maybe something that could lead to another book!