“Usefulness is inversely proportional to status,” Deyan Sudjic writes in his new book “The Language of Things: Understanding the World of Desirable Objects.” “The more useless an object is, the more highly valued it will be.”

The author is referring to the relative value of art versus industrial design – but the observation can be applied equally well to cities such as San Francisco. Think about it: The physical need to occupy a specific patch of earth has never been less important to one’s success. Everything we might acquire can be tracked down online; most culture we seek can be procured through a handheld device. Our 21st century equivalent of an office tower turns out to be a cafe with free Wi-Fi.

All this should signal a death knell to the traditional core. Instead – recession aside – marquee hubs such as San Francisco stand more desirable than ever. It’s not that we need to be here. But the center serves as a stage set, the spotlit focus for people who use urbanity to define themselves and their tribe.

Cities aren’t the focus of Sudjic’s book, a well-tailored provocation that both explores why the best design work is timeless and decries how it can be debased for status or show. Thomas Chippendale and his 18th century furniture are explored as a precursor to Ikea – “a pioneer in brand creation” – and the ever-shinier line of Apple products is contrasted with the demise of the fountain pen as status symbol (“the basic concept has lost its relevance”).

The underlying theme: the quest among designers and clients for “emotional resonance,” the design of a watch or a laptop computer that connotes something beyond what it does: “to provide us with a reminder of the world beyond utility.” Which brings us back to downtown San Francisco, where so much of the terrain is fine-tuned to make you feel like something is happening – and that you belong in/to the scene.

“In objects we value the ‘authentic,’ the hand-pressed. It’s often the same thing with cities,” Sudjic said in a telephone interview last week. “A (successful) city is about how it feels to be in a particular place, at a particular time.”

Before assuming his post as director of London’s Design Museum in 2006, Sudjic was architecture critic for the Observer, a British daily where he provided uncommonly lucid takes on how the “art” of architecture is imbued by what he described in his final column as “the hard stuff of power, politics and city building.”

It’s a mix that’s never static – just as designers seek out new emotional cues, and as neighborhoods are redefined again and again. As long as that’s the case, the appeal of high design and urban centers is likely to endure. Whether they’re “needed” or not.

The Language of Things: Understanding the World of Desirable Objects: By Deyan Sudjic. W.W. Norton, 208 pages

By John King, SFgate; excerpts, edited by ELLOPOS BLOG