The Appeal of Direct Manipulation

Once upon a time, the text displayed on-screen in a word processor didn't match the printed output. So if WYSIWYG word processors are so dominant, why do many people still hand-code HTML? The first reason is that HTML output is not consistent, so visual HTML editors are WYSIWYMGISB (What you see is what you might get in some browsers). More importantly, HTML is much more nuanced than plain text. The ability to directly manipulate the exact HTML code affords coders the precision they want.



But there is a more fundamental psychological reason why some people prefer direct manipulation. Direct manipulation is hard-wired into our brains at a more primitive level than abstract representations. Although higher intelligence is often measured by the abililty to perform abstract tasks (using maps, language, and other symbols), humans favor direct manipulation when it is available.



The famous architect Antonin Gaudi spent hours molding clay as a child. By mastering direct manipulation of his physical reality, he enhanced his ability to work with abstract designs. (Gaudi designed several famous buildings in and around Barcelona, including a church named "La Sagrada Familia." His architecture is very surreal, almost molten, and he influenced surrealist painters such as Dali.)



My 4-year old daughter has a marionette. Instead of manipulating it via its strings, she grabs the puppet's body directly. It isn't simply that indirect manipulation (in this case using the "handle" to control the strings) is physically more difficult. It is a layer of mental abstraction that isn't necessary, because she isn't trying to maintain the illusion that there is no puppeteer. Hence, she has no incentive to use the marionette's strings.



The power of today's more complex WYSIWYG tools, such as page layout programs, is that they simulate direct manipulation during composition, not just during output. Therefore, complex interfaces would be better thought of as SPRTDM (Simulating physical reality through direct manipulation) than WYSIWG. Interface designers should remove those abstractions that hinder direct manipulation by the user. Because there is no real-world physical manipulation in some applications (such as sound editing) some software will always require human-engineered abstractions.



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