How Many Languages is it Possible to Know?


There are millions of people, even in the mostly monolingual US, who speak more than one language at home. Competence in three languages is not unusual, and we've all heard stories of grandmas and grandpas who had to master four or five languages on their way from the old country to the new. In India it is common for people to go about their business every day using five or six different languages. But what about 10, 20, 30, 100 languages? What's the upper limit on the number of languages a person can know?

Michael Erard, in his fascinating book Babel No More, travels around the world in search of hyperpolyglots, people who study and learn large numbers of languages. He sheds light on the secrets of their success, and explains why it can be hard to put an exact number on language knowledge. Here are some of the hyperpolyglots he meets:

Graham Cansdale, 14 languages.
Cansdale uses all 14 languages professionally as a translator at the European Commission in Brussels. He has studied more languages.

Lomb Kató, 16 languages.
This Hungarian polyglot said five of these "lived inside" her. Five others needed at least a half day of review in order to be reactivated, and with the six remaining she could do translation. Confidence, she claimed, was crucial to language learning. Her study tip: "Be firmly convinced you are a linguistic genius."

Alexander Arguelles, 20 languages or so.
Arguelles declines to say the exact number. "If someone tells you how many languages they speak, then you shouldn't trust them," he says. He has studied more than 60 languages and devotes 9 hours of study every day to them. Twenty is the number of them in which he has reading competence.

Johan Vandewalle, 22 languages.
In 1987, Vandewalle won the Polyglot of Flanders contest, where he was tested in 22 languages (though he has studied more). The contest required 10 minute conversations with native speakers, with 5 minute breaks in between.

Ken Hale, 50 languages.
The famous MIT linguist said he could "speak" only three languages (English, Spanish, Warlpiri), and could merely "talk in" others. He considered the ability to speak a language to include knowing all its cultural implications. He didn't like people perpetuating the "myth" of his language feats, though many colleagues had observed him do things like study a grammar of Finnish on an airplane and start speaking it easily upon arrival.

Emil Krebs, 32 to 68 languages.
The number depends on who's counting. A German diplomat who worked in China, Krebs had such an unusual talent for languages that after his death his brain was preserved for study.

Cardinal Giuseppe Mezzofanti, 40 to 72 languages.
One of his biographers broke it down as follows: he had 14 which he had studied but not used, 11 in which he could have a conversation, 9 which he spoke not quite perfectly but with a perfect accent, and 30 languages (from 11 different language families) which he had totally mastered.

Stories of Mezzofanti's language prowess are so legendary, they may be merely legends. But it is clear from Erard's time among the hyperpolyglots that with the right kind of natural talent, motivation, and hard work, remarkable feats can be accomplished. The psycholinguists Erard talked to said there was "no theoretical limit to the number of languages one could learn." There was only the limitation of time.

But most of the hyperpolyglots themselves were reluctant to claim too many, even when they had studied dozens. This is because they have a finer definition of "knowing" a language than most people, and the humility that comes from becoming an expert: The more you know, the more you know what you don't know. Among the hyperpolyglots, 15 seems to be about the high end when it comes to the number of languages they are willing to vouch for in themselves. Even so, the 30 or so other languages with which they may have some lesser familiarity are probably still better than your high school Spanish.

Full vs. Queen Mattress: What's the Difference?

If you’re in the market for a new mattress this Presidents Day weekend (the holiday is traditionally a big one for mattress retailers), one of the first decisions you’ll need to make is regarding size. Most people know a king mattress offers the most real estate, but the difference between a full-sized mattress and a queen-sized one provokes more curiosity. Is it strictly a matter of width, or are depth and length factors? Is there a recommended amount of space for each slumbering occupant?

Fortunately, mattress manufacturers have made things easier by adhering to a common set of dimensions, which are sized as follows:

Crib: 27 inches wide by 52 inches long

Twin: 38 inches wide by 75 inches long

Full: 53 inches wide by 75 inches long

Queen: 60 inches wide by 80 inches long

King: 76 inches wide by 80 inches long

Depth can vary across styles. And while you can find some outliers—there’s a twin XL, which adds 5 inches to the length of a standard twin, or a California king, which subtracts 4 inches from the width and adds it to the length—the four adult sizes listed above are typically the most common, with the queen being the most popular. It's 7 inches wider than a full (sometimes called a “double”) mattress and 5 inches longer.

In the 1940s, consumers didn’t have as many options. Most people bought either a twin or full mattress. But in the 1950s, a post-war economy boost and a growing average height for Americans contributed to an increasing demand for larger bedding.

Still, outsized beds were a novelty and took some time to fully catch on. Today, bigger is usually better. If your bed is intended for a co-sleeping arrangement with a partner, chances are you’ll be looking at a queen. A full mattress leaves each occupant only 26.5 inches of width, which is actually slightly narrower than a crib mattress intended for babies and toddlers. A queen offers 30 inches, which is more generous but still well below the space provided by a person sleeping alone in a twin or full. For maximum couple comfort, you might want to consider a king, which is essentially like two twin beds being pushed together.

Your preference could be limited by the size of your bedroom—you might not be able to fit a nightstand on each side of a wider bed, for example—and whether you’ll have an issue getting a larger mattress up stairs and/or around tricky corners. Your purchase will also come down to a laundry list of options like material and firmness, but knowing which size you want helps narrow down your choices.

One lingering mystery remains: Why do we tend to shop for mattresses on Presidents Day weekend? One reason could be time. The three-day weekend is one of the first extended breaks since the December holidays, giving people an opportunity to trial different mattress types and deliberate with a partner. Shopping Saturday and Sunday allows people to sleep on it before making a decision.

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Do Mission Control Personnel Go Through as Many Simulations as Astronauts?

David McNew, Getty Images
David McNew, Getty Images

Jared Olson:

Mission control personnel go through a lot more simulations than astronauts, as the flight controller needs to develop very specialized skills and knowledge. On the other hand, astronauts in general need to develop the appropriate depth of knowledge across many disciplines. So shorter classes targeted to their needs are used instead to make the best use of their limited time.

I was the robotics instructor for the EVA simulation (or sim) yesterday and the rig (the simulator system) was not behaving for me. Things were up and running quickly, but after I simulated the main robotics computer having a fatal software fault things went downhill. The team rebooted it to recover, as expected, but the rig did not cleanly handle the reboot.

Suddenly it would not accept any commands to the robot arm. The hand controllers were not communicating. And the astronauts' laptop would not connect.

Eventually, I ran out of troubleshooting options and had to tell my three robotics flight controllers in training that all this was unplanned and the sim was not going to go as expected for them. Other disciplines had "scripting priority," as there were controllers who were assigned to use this sim as an evaluation toward their certifications. I did not have the leverage to disrupt the sim by halting the rig to reset the robotics simulator.

Flight controllers go through so many sims partly because of days like this—where, for whatever reason, they don't get as much "content" as we'd like. I told my guys to greencard that the arm simulator was working as expected, which means that they had to pretend they were seeing all the telemetry indications that would normally happen for the arm supporting an EVA. Basically: Just follow along and pretend.

Each simulation is unique in terms of the coordination required with other disciplines, the malfunctions they get to work through, and the timing involved in planning. Throughout their training flow they need to display their ability to work through a broad enough variety of cases before we can call them "certified." How much they get out of each sim can be a roll of the dice.

This post originally appeared on Quora. Click here to view.