Until the early 17th century, it was considered good English table manners to stab your meat with a knife, then rip it apart with your hands. Why use a fork - that newfangled Continental invention - when you could just as easily use your fingers? It took 100 years before good manners made forks de rigueur at the table.

Then, innovation pretty much stopped.

At the International Home and Housewares Show next week in Chicago, 28-year-old Wichita inventor Mike Miller will try to change that. His product, the Knork, is a knife-fork that looks like any other fork but can easily cut through a raw carrot. Despite its name, the Knork is far more ingenious than the retro but not terribly useful spork (spoon-fork) or the splayd (spoon-blade), neither of which really caught on. Miller, who is in discussions with a national retailer, says the Knork could be the answer for cutting your food on airplanes, for the blind or disabled or for just eating in front of the TV.

Miller is one of about 2,000 vendors going to the show with hopes of selling the next big thing. But it's not just numerical odds that are against the Knork becoming this year's DustBuster, breadmaker or pod coffee machine - all products that made a splash at the annual event. It's history. For centuries, designers have sought to improve the fork, knife and spoon. All have remained stubbornly unchanged.

However, in an ever more casual and fast-paced world, a new era of cutlery could be dawning. Technology and production methods have evolved so that flatware no longer has to be flat. Culture, too, is changing. Hard data are sparse, but a U.K. survey by grocery store Sainsbury's revealed that only 10 percent of 18- to 34-year-olds in Britain use a fork, knife and spoon at dinner, while 10 percent skipped cutlery entirely and ate with their hands.

"Cutlery has always been dictated by culture, not common sense," said Donald Norman, a professor at Northwestern University and the author of "The Design of Future Things." "We're much less formal. Even formal dinners are much less formal."

CULTURAL SHIFT

A century ago at formal meals in Western society, diners used 12 or more utensils. Today, a standard formal place setting is five pieces.

Shifts in culture and fashion have done far more to dictate changes to eating utensils than utility or ergonomics. In the Middle Ages, knives were designed with sheaths for easy transport, as silverware was too expensive for innkeepers or hosts to provide it to their guests. In the late 1500s, when stiff lace collars called ruffs came into fashion, most spoons had short stems. The stems were made longer to get the food past the collars and into people's mouths.

It is said that it was sheer force of personality that erased early knives' dagger-sharp points. In the early 1600s, Cardinal Richelieu, the French king's first minister, ordered all the knives in his palace ground down to prevent his guests from the common but unseemly habit of picking their teeth, according to Henry Petroski's "The Evolution of Useful Things."

In contrast, design innovations, even clever ones, tend to make limited headway. The spork, for example, has been around since at least the 19th century - the first patent was registered in 1874 - but remains a novelty. The same goes for more modern innovations such as Michael Schneider's sexy Zeug "tools," which are based on primitive cave-man designs; the spoon scoops liquid like an oyster shell, and the knife is modeled on a honed flint. Next up: the Museum of Modern Art's ramen spoon, a traditional spoon crowned with four tines, which goes on sale in May.

"Cutlery took centuries to catch on. The fork was particularly unwieldy and hard to use. It was societal aspiration that persuaded people to learn," said Darra Goldstein, a professor at Williams College and the curator of "Feeding Desire: Design and the Tools of the Table, 1500-2005" a 2006 exhibition at the Cooper-Hewitt National Design Museum in New York.

IDEA LONG IN THE WORKS

A cultural shift is what Knork inventor Miller tapped into when he conceived of the utensil back in the eighth grade. After a basketball game, he was struggling to cut a very hot slice of pizza with a fork. Because forks are stamped from a piece of stainless steel, they are the same thickness throughout, and no amount of sawing would easily cut through his crust. The same was true, he realized, when you ate standing up at a party or on your lap on the living room sofa.

At 14, there wasn't much Miller could do, but he never forgot his big idea. During college, he began to experiment with an improved design. He borrowed a few forks from his mom's silverware drawer and used Bondo, an automotive putty, to reshape them. He added thicker areas to provide leverage and a smooth beveled edge to cut through food.

At 21, with a design in hand, he signed on a few investors and had a prototype made - "$800 for a fork," Miller remembers. But the issue has always been "getting it into a consumer's hand so they can try it. That's when they realize how different, how useful it is."

Miller said that he has sold about 1 million Knorks at 500 independent retailers and online. But persuading people to try something new is a battle. After several years in business, Miller realized he couldn't sell the Knork individually, so he designed a complete set of flatware.

And even those who try it might not see the benefit: Nancy Pollard, owner of La Cuisine cookshop in Alexandria, Va., tested the Knork on a thin slice of grilled steak and salad and found that it cut only slightly better than a regular fork. In addition, she found that the upward tilt of the tines could scrape the top of her mouth.

"It's a little better, but not good enough for me to make a change," she said.

Technology advances also are driving designers to experiment. Mark Wilson, a Charlottesville, Va., architect, uses 3-D modeling software - a version of what architect Frank Gehry uses to craft his sinuous masterpieces - to create his Curvware cutlery. Rather than gripping the utensils, diners pinch each piece between their index fingers and thumbs. The design, ergonomists say, requires "minimum gross motor movements" and therefore makes the utensils more comfortable and efficient.

"Thanks to production methods, we've all got the wagon wheel instead of radial tires," Wilson said. "Computers now let us design more exotic shapes. All I have to do is send the file to a manufacturer who can cut it to my specifications."

NEW DESIGNS TAKE TIME

It's not often you see people looking at their fork, muttering: "We can put people on the moon, but, boy, this silverware is awkward!" But Wilson says there are dozens of common designs that could - and should - be improved. Flatware as we know it is functional but far from thoughtfully designed: "We could all drive Buicks. They go from point A to point B," Wilson said. "But a lot of us still want and pay for the Mercedes."

Wilson's design is more comfortable, especially for diners who eat European-style, not swapping the utensils from hand to hand after cutting, and keeping the fork facing downward.

Wilson got a patent in 1992, but he only recently began to seriously market the product. Bebo Trattoria's Roberto Donna is a fan, and Curvware is used at the Italian Culinary Institute for Foreigners. A set was also on display at the Cooper-Hewitt's "Feeding Desire" exhibit.

Like Miller, Wilson says trying is believing. Instead of mass-marketing his product, he's setting up Tupperware-esque parties at fancy restaurants where guests can try and then, he hopes, buy the product. It's a smart strategy, said author Norman: Early adopters are trendsetters who don't care about price. They'll pay for something cool and then spread the word.

Still, Norman and others are skeptical that new designs - even really excellent ones - will make quick inroads. A lot of designs are just "good enough," Norman said. Take the qwerty keyboard. There are better keyboards that are faster and easier to learn, but not if you've made a habit out of the traditional one.

"When new innovation arrives, it takes decades before it's accepted," Norman said. "Not months. Decades."

Knork flatware is available at www.knork.net ($27.50 for a five-piece place setting.) Curvware: www.curvware.com ($99 for a three-piece place setting). Museum of Modern Art's ramen spoon: www.momastore.org ($12, on sale beginning in May). Mono Zeug tools: www.unicahome.com ($225 for a four-piece place setting).