Advertisement

Summary
Ward Cunningham talks with Bill Venners about complexity that empowers versus complexity that creates difficulty, simplicity as the shortest path to a solution, and coding the simplest thing when you're stuck.

In the software community, Ward Cunningham has a reputation for being a font of ideas. He invented CRC Cards, a technique that facilitates object discovery. He invented the world's first wiki, a web-based collaborative writing tool, to facilitate the discovery and documentation of software patterns. Most recently, Cunningham is credited with being the primary inspiration behind many of the techniques of Extreme Programming.

On September 23, 2003, Bill Venners met with Ward Cunningham at the JAOO conference in Aarhus, Denmark. In this interview, which will be published in multiple installments on Artima.com, Cunningham gives insights into wikis and several aspects of Extreme Programming.

• In Part I: Exploring with Wiki, Cunningham discusses using wiki for collaborative exploration and the tradeoff between wiki authors and readers.
• In Part II: Collective Ownership of Code and Text, Cunningham discusses how he designed wiki to be a model for collective code ownership, collective incentives for pride of ownership, and how to deal with disagreements by eliminating the cost of making mistakes.
• In Part III: Working the Program, Cunningham discusses the flattening of the cost of change curve, the problem with predicting the future, and the program as clay in the artist's hand.
• In Part IV: To Plan or Not to Plan, Cunningham discusses using the programming language, rather than the whiteboard, to design and communicate ideas.
• In this fifth and final installment, Cunningham discusses complexity that empowers versus complexity that creates difficulty, simplicity as the shortest path to a solution, and coding the simplest thing when you're stuck.

Complexity that Empowers

Bill Venners: What is simplicity? How do we recognize it when we see it? And why should we strive for it?

Ward Cunningham: I actually enjoy complexity that's empowering. If it challenges me, the complexity is very pleasant. But sometimes I must deal with complexity that's disempowering. The effort I invest to understand that complexity is tedious work. It doesn't add anything to my abilities.

A friend of mine once said that there are problems and there are difficulties. A problem is something you savor. You say, "Well that's an interesting problem. Let me think about that problem a while." You enjoy thinking about it, because when you find the solution to the problem, it's enlightening.

And then there are difficulties. Computers are famous for difficulties. A difficulty is just a blockage from progress. You have to try a lot of things. When you finally find what works, it doesn't tell you a thing. It won't be the same tomorrow. Getting the computer to work is so often dealing with difficulties.

The complexity that we despise is the complexity that leads to difficulty. It isn't the complexity that raises problems. There is a lot of complexity in the world. The world is complex. That complexity is beautiful. I love trying to understand how things work. But that's because there's something to be learned from mastering that complexity.