The law of conservation of complexity, also known as Tesler's Law, or Waterbed Theory, is an

adage An adage (; Latin: adagium) is a memorable and usually philosophical aphorism that communicates an important truth derived from experience, custom, or both, and that many people consider true and credible because of its longeval tradition, i.e. ...

human–computer interaction Human–computer interaction (HCI) is research in the design and the use of computer technology, which focuses on the interfaces between people (users) and computers. HCI researchers observe the ways humans interact with computers and design tec ...

stating that every

application Application may refer to: Mathematics and computing * Application software, computer software designed to help the user to perform specific tasks ** Application layer, an abstraction layer that specifies protocols and interface methods used in a c ...

has an inherent amount of

complexity Complexity characterises the behaviour of a system or model whose components interaction, interact in multiple ways and follow local rules, leading to nonlinearity, randomness, collective dynamics, hierarchy, and emergence. The term is generall ...

that cannot be removed or hidden. Instead, it must be dealt with, either in product development or in user interaction. This poses the question of who should be exposed to the complexity. For example, should a software developer add complexity to the software code to make the interaction simpler for the user or should the user deal with a complex interface so that the software code can be simple? __TOC__

Background

While working for

Xerox PARC PARC (Palo Alto Research Center; formerly Xerox PARC) is a research and development company in Palo Alto, California. Founded in 1969 by Jacob E. "Jack" Goldman, chief scientist of Xerox Corporation, the company was originally a division of Xero ...

in the mid-1980s,

Larry Tesler Lawrence Gordon Tesler (April 24, 1945 – February 16, 2020) was an American computer scientist who worked in the field of human–computer interaction. Tesler worked at Xerox PARC, Apple, Amazon, and Yahoo! While at PARC, Tesler's work include ...

realized that the way users interact with applications was just as important as the application itself. The book ''Designing for Interaction'' by Dan Saffer"Designing for Interaction" by Dan Saffer at amazon.com
/ref> includes an interview with Larry Tesler that describes the law of conservation of complexity. The interview is popular among user experience and interaction designers.

argues that, in most cases, an engineer should spend an extra week reducing the complexity of an application versus making millions of users spend an extra minute using the program because of the extra complexity. However,

Bruce Tognazzini Bruce "Tog" Tognazzini (born 1945) is an American usability consultant and designer. He is a partner in the Nielsen Norman Group, which specializes in human-computer interaction. He was with Apple Computer for fourteen years, then with Sun ...

proposes that people resist reductions to the amount of complexity in their lives.The Complexity Paradox, by Bruce Tognazzini
/ref> Thus, when an application is simplified, users begin attempting more complex tasks. Many other consultants, however, have stated on social media that this is not a law at all. While acknowledging the tradeoff between how the software is built and how it is used happens, it is not inherent. Instead, it is mostly due to a poor architecture and not attending to the customer journey the product is in.

Applications

Possible applications of Tesler's Law: *Programming *Vehicles *Home appliances *Workplace equipment

References

External links

{{DEFAULTSORT:Law Of Conservation Of Complexity Human–computer interaction Software engineering folklore