You can’t talk to people in Silicon Valley anymore. They don’t even speak our language.

By that, I’m not referencing Mark Zuckerberg’s mediocre Mandarin or the software code underlying so much of the Valley’s endeavors. I’m talking, literally, about the words Valley denizens use when they speak, in sentences like: “Yeah, that start-up has some cool gamification, but it’s an X for Y model, they don’t even have a minimum viable product, and that space is already in Hype Cycle. Their only hope is to pull off an acqui-hire. And even then, I don’t know if they have a total addressable market.”

In other words (rough translation of above sentence: that start-up is a cool place to work but needs to buy another company or it’ll die), our technological masters no longer speak the same language that most Californians do. And that is just one sign of a growing divide between tech and non-tech that isn’t good for the state.

The Valley’s growing cadres of wealthy and powerful technocrats have turned the Bay Area into an island, cut off from the rest of struggling California. Their outlook and lives are global, while the rest of us exist locally. There are chasms between their technological sophistication and ours, between their venture-backed business methods and our adherence to more established principles of accounting, and between our ethnic and gender diversity and their lack of it.

Yes, they welcome our dollars, app downloads, and posts of baby pictures, but they don’t really invite us in to talk. Instead, they’ve built a wall—of jargon—that keeps us at a distance.

As a frequently bewildered visitor to Silicon Valley, I have felt this firsthand. But I didn’t undertsand the full extent of this language barrier until reading Rochelle Kopp and Steven Ganz’s new book, Valley Speak: Deciphering the Jargon of Silicon Valley.

Kopp and Ganz, both longtime Silicon Valley residents, told me by phone that they wrote the book to help people who want to work in or do business with Silicon Valley but bump up against its jargon, which they call “mind-numbing” and “impenetrable at best, and at worst downright ridiculous.”

HBO’s Silicon Valley.

The best evidence of the problem is that the book has 100 chapters, covering hundreds of terms, from “Agile Development” to “Unicorpse.” Kopp and Ganz say that Silicon Valley’s jargon does tend to exclude people, though they believe it isn’t intentional. Instead they suggest Silicon Valley dialect is in part the by-product of Bay Area crowding, with people living and working in cramped quarters that bind them together while sometimes shutting out the rest of the world.

“There are so many great things happening here—it would be great if the conversation were more open,” Kopp says. With jargon, “there’s a big element of ‘this is a private club, and you either know what people are talking about or you don’t,’ and that really marks you. I was at brunch where one of the people was a twenty-something engineer from the Midwest, and he asked at one point, ‘What’s a unicorn?’ And I told him don’t ever say that out loud again.” (A unicorn is a start-up whose valuation exceeds $1 billion).

The authors report that the language barrier can be a real problem for Silicon Valley’s globally oriented enterprises; Kopp says she decided to write the book in part because she worked with Asian entrepreneurs who couldn’t understand what potential Valley partners were saying. And given Silicon Valley’s importance to California’s economic future, it’s important to break those barriers down.

But does Silicon Valley want them down? As a journalist who receives dozens of pitches a week from Valley companies looking for publicity, I’m struck by how reflexively Silicon Valley enterprises use jargon to obscure what their companies actually do. The most absurd such Silicon Valley pitch of the spring came from a “serial entrepreneur” touting a “revolution” for tech workers — which turned out to be an overnight bus service from San Francisco to L.A. for $65 that offers the supposed innovation of saving you time by replacing the hassle of an hour-long airplane flight with a seven-hour bus ride. (You can do the same trip for $22 on Greyhound, which has free Wifi).

I also wonder if jargon isn’t a cover for old-fashioned hype and even con-artistry. Stupid money, from places like New York and Hollywood, is still flowing into a Silicon Valley that seems ripe for a crash. And it can be hard to spot scammers in Silicon Valley’s sea of start-up failures.

At root, though, the language barrier is a monument to Silicon Valley’s sense of self-importance. Powerful people, especially those who create new products and companies and services, tend to put their names on things. Silicon Valley’s fondness for inventing new language tracks with its self-image as a place that is changing the world.

The downside to that is a loss of perspective (not everything is revolutionary or disruptive). And that loss of perspective shows itself in the decline in the Valley’s sense of humor. A UCLA economist who writes about the Valley recently mentioned to me that Google never says or does anything remotely funny. (I checked—he’s right). It’s telling that the HBO comedy Silicon Valley derives most of its humor from how ridiculously seriously tech people take themselves.

When I recently asked aloud on Twitter whether the Valley had lost its sense of humor, no one disputed the premise. Elliot Loh, a designer and an incubator co-founder, replied, “Like any of the products we build, our jokes will launch next quarter.”

Of course, Silicon Valley is very powerful, and it’s easier to be funny when you’re the underdog. The most powerful companies in the Valley also face pressure to project neutrality; note the criticism Facebook has faced over whether its trending stories choices are infected by political bias.

It’s true that executives like Zuckerberg or Apple’s Tim Cook are more outspoken than the average corporate titan, especially when it comes to supporting liberal cultural values that are broadly shared in the Valley. And the tech investor Sean Parker has become one of California’s top political donors.

But these men attract attention because they are exceptions. Valley types are far more likely to engage internationally—on privacy or climate change issues—than they do here at home in California. The Valley doesn’t often raise its voice on the fundamentals of state governance—school funding, health care, prisons, and public universities. And that lack of engagement is one reason why a California with so much private wealth has such weak and undernourished public services.

Of course, engagement is difficult these days. Our political and civic worlds are nasty and angry places, in no small part because of Facebook, Twitter, and other platforms that the Valley has created. So it’s no surprise that people in Silicon Valley, like so many of us, are turning inward and talking mostly to themselves.