Mr Streitz—in fact, I should actually address you as Dr Dr as you hold two Ph.D.s, one in physics, specifically theoretical physics, and one in psychology, or cognitive psychology to be precise.
How did you come to study these two very different fields and then to such an advanced level as to write a dissertation in each?

Dr rer. nat. Dr phil. Norbert A. Streitz

I have been asked about this quite often. A detailed explanation would take too long, so I will give you the Reader’s Digest version. At school I was very much interested in natural sciences, so I studied physics, mathe­matics and chemistry, first gaining a diploma degree in physics. In my doctoral dissertation I focused on Einstein’s theory of general relativity, and this inevitably brought up some philosophical and epistemological questions, i.e. relating to theories of knowledge. In parallel, I was also interested in the problem-solving processes of scientists: for example, knowing what happens at a cognitive level when a mathematician sets about proving a theory and completes it successfully with Q.E.D. (quod erat demonstrandum, meaning “thus it has been demonstrated”). I therefore contacted the psychology research department at my university in Kiel and signed up for psychology in parallel, studying models of human problem-solving behaviour. In the end, I made psychology one of my two minor fields in my oral doctoral examination for my major in physics.

 

Afterwards, I went to the University of California in Berkeley, USA, as a postdoctoral fellow in the sciences. Using experimental methods, we investigated and compared how physics problems were solved by experts (professors, which also included some Nobel Prize winners) and beginners (students). In the USA, the field of cognitive science was just emerging, combining psychology, linguistics, neuroscience and computer science, especially artificial intelligence. On my return to Germany, I accepted an offer from the Institute of Psychology at the Technical University RWTH Aachen for research and teaching in the area of experimental cognitive psycho­logy. In this role, I applied my knowledge from physics about modelling and worked with my students to develop computer simulations of cognitive processes. After some time, I was told: “If you want to be successful in psychology, you will also need to have a Ph.D. in the subject.” This is rather a typical German attitude, and so I wrote my second dissertation on the subject of cognitive science and knowledge representations.

 

 

 

 

However, in your work you have not remained solely in the field of psychology, but switched your attention to another area also of great relevance to our conversation today as well—namely, software ergonomics and more generally, designing the human-computer interaction.

Dr rer. nat. Dr phil. Norbert A. Streitz

That’s right. The area of human-computer interaction was still very new back then, but at the same time the logical further development of my psychological research. Inspired by the proliferation of the personal computer, we investigated how people solve problems with the help of computers. The interface between people (as users) and the computer needs to be designed in such a way that it enables them to concentrate mainly on the problems to be solved, while the interaction with the computer, especially the software, should not constitute a barrier. In the mid-1980s, we founded—in analogy to the field of hardware ergonomics—­the special interest group on Software Ergonomics within the German Informatics Society (“Gesellschaft für Informatik”). We specifically configured it as an inter­disciplinary cooperation between computer scientists, psychologists, ergonomists and designers. To explore these issues in a wider context, I moved in 1987 to the newly established Institute for Integrated Publication and Information Systems (IPSI) of the GMD in Darmstadt, to help set it up and advance research as Division Manager and Deputy Director of the Institute.

 

The design of software and interaction with computers present new challenges for all, including, and es­pecially designers. Even then, our credo was that people should be at the heart of all considerations, summarized as human-centred design. Later, I added the claim keep the human in the loop, which is becoming ever more important in the context of smart environments, such as the smart home, and corresponding automation trends.

 

Unfortunately, despite all the progress in areas such as touch-sensitive surfaces, for example, the viewpoint of human-­centred design is not yet entirely widespread. Swiping a surface is not yet user-oriented per se. There are still many product developments which are primarily technology-driven, especially when we move away from the consumer product segment and turn to professional applications in the working world. There are often great discrepancies between the user experience in leisure applications as against in working life, in situations such as a bank, an insurance company or in an enterprise resource planning system.

 

Back then, I was already a staunch advocate of the concept that computers should be in the background as devices, because the real issue is designing the human-problem interaction. We called this Cognitive Ergonomics. In early 2000, we put this topic forward more fundamentally with the concept of the Disappearing Computer. This was also the name given to a comprehensive EU-funded Proactive Research Initiative of 17 projects, for which I had the honour and responsibility of being the Chair of the Steering Committee.

 

 

 

 

“Disappearing Computer” is a great term. However, if we look at the situation today,
we do not get the sense that the computer is disappearing.

Quite the opposite, in fact; they seem to be multiplying, and this trend only looks set to be further intensified
by the widely propagated digitisation of all industry sectors.

What are your thoughts?

Dr rer. nat. Dr phil. Norbert A. Streitz

The concept of the Disappearing Computer is not about reducing the number of computers, but ensuring that these devices disappear into the background. I would make a distinction in this regard between ­physical ­disappearance in the sense of being invisible (by being integrated in the environment) and mental disappearance, whereby technology is integrated, but remains visible. Nevertheless, the fact that we are interacting with a computer is mentally dismissed. Interaction should be understood as interaction with an artefact, albeit with a smart artefact. The future lies in interaction with a smart environment, perhaps even to the extent that smartphones become superfluous.