Vivek Haldar

The Cognitive Style of Unix

One of the most deeply held beliefs in the culture of *nix (and everything that springs from it) is that the steep learning curve pays off. Yes, the tools seem cryptic and “hard-to-use”, with hardly any crutches for the beginner. But if you stick with it and keep learning you will be rewarded. When you grok the power of economical command lines, composability and extensibility, you’re glad you didn’t run back to the arms of the GUI on the first day. It was worth it.

There is another belief that goes deeper, and it is the reason that after decades of existence and millions of newbie-suffering-hours, the learning curve has not become any easier, or gone away. That belief is: the learning curve has value, it is essential for learning, and it needs to be preserved, not whittled away in the name of “ease-of-use.” 1

I recently came across some research which rigorously backs up this line of thinking.

Dr. Christof van Nimwegen 2 is a cognitive psychologist researching user interface issues. He has published several papers 345, leading up to a doctoral dissertation 6, that investigate how cues in software interfaces affect how people solve problems and interact with those interfaces.

He frames the issue in terms of internalization vs externalization. Some software tries to be “easy-to-use” by externalizing rules and knowledge into the interface, so that the user does not have to think and can merely follow the cues. An example is inactivating parts of the interface that are not relevant or allowed in a particular context. Software that does not externalize such rules and knowledge relies instead on the user internalizing those, and mindfully coming up with plans to solve the problem at hand.

The traditional belief is that internalization is slow at first, but faster and more powerful as time goes on, whereas externalization helps newbies come up to speed fast and eventually approach guru-level. That belief translates to the following learning curve:

However, Nimwegen’s studies reveal the following curve:

From the paper:

Our first hypothesis stating that internalization leads to more planning and better performance is supported. Internalization resulted in longer thinking times before starting to work on the problem and to more time between moves. It indicates that when information has to be internalized, more contemplation is provoked and users ponder longer before acting… Internalization subjects solved the problems with fewer superfluous moves, thus with greater economy… Our results suggest that internalization provokes more “thinking before acting” than externalization.not at any measure, externalization resulted in better performance. Once more we found positive effects of internalization on problem-solving behavior: it led to more plan-based behavior, smarter solution paths and better declarative knowledge. Externalization led to a more display-based approach resulting in less economic solutions and shallower thinking.

(emphasis mine)

Their recommendation is less assistance:

Designers could consider making interactions “less assisted” to persuade users into specific behavior. This issue is beyond plain usability issues and focuses on more meta cognitive aspects of interface-induced behavior such as planfulness and user engagement.

Another benefit of internalization was that interruptions were less disruptive.

…after the interruption, internalization-subjects kept improving, while externalization fell back… internalization-subjects continue to work on base of the plan-based strategy as they did before, while externalization on the other hand performs worse after interruption. They fell back depending on the interface, having a less elaborated plan.

Internalization was also helpful in retaining knowledge.

The third hypothesis in which we expected that internalization would remember more knowledge elements was supported. We assumed that internalization- subjects had to build a stronger, more elaborated plan and could rely less on interface information, and indeed working with the internalized version resulted in having significantly better knowledge of the problems rules and problem space. There was also the tendency that internalization-subjects rated the clarity of the rules higher.

1 Neal Stephenson’s “In the beginning was the command line” is a deep and thoroughly enjoyable exploration of this topic.


3 Christof van Nimwegen, Herre van Oostendorp, Daniel Burgos, and Rob Koper. 2006. Does an interface with less assistance provoke more thoughtful behavior? Proceedings of the 7th international conference on Learning sciences (ICLS ‘06). International Society of the Learning Sciences 785-791.

4 Nimwegen, C. van; Oostendorp, H. van; Tabachneck-Schijf, H.J.M. 2005. The role of interface style in planning during problem solving. Proceedings of the 27th Annual Cognitive Science Conference, (2005), pp. 2271-2276

5 van Nimwegen, C.; van Oostendorp, H.; Schijf, H.J.M.T.; , “Externalization vs. internalization: the influence on problem solving performance,” Advanced Learning Technologies, 2004. Proceedings. IEEE International Conference on , vol., no., pp. 311- 315, 30 Aug.-1 Sept. 2004 PDF

6 The paradox of the guided user: assistance can be counter-effective (2008)