Why are languages spoken at different speeds?
Have you ever changed audio languages in the middle of a movie? Although foreign languages still sound fast to untrained ears, when you switch between Thai, Japanese, and English, you listen to languages spoken at wildly different speeds.
In this article, we explore why the speed of languages varies and how the invisible aspects of how we communicate mean that we all get our message across at roughly the same time.
Which language is fastest?
A 2011 study measured the speech rate of seven languages, with Japanese topping the list. The researchers found that Japanese speakers averaged 7.84 syllables per second, while English speakers averaged only 6.19 syllables per second.
This makes sense if you think about how these languages are spoken. English has many syllables containing many sounds. Try saying “The smart frogs jumped twelve fast sticks” as quickly as possible. This short sentence contains 29 different phonemes – the basic sound units of a language – while using only six syllables. The syllables of many languages, such as Japanese, contain only a few sounds, allowing more syllables to be produced per second.
What is the fastest language in the world? #language #languages
Each language is spoken at a slightly different speed. Video: What is the fastest language in the world?, @VLingvo
This means that Japanese is about 20% faster than English. But despite this, Japanese and English speakers can watch the same dubbed movie for the same length of time. This is partly due to creative audio dubbing, but also to differences in how the two languages convey meaning.
Different languages always communicate information at the same speed
In the mid-20th century, American mathematician Claude Shannon made enormous contributions to mathematics, electrical engineering, and computer science through his work on information theory. Shannon, who introduced the term “bit” to refer to units of information in computing, explored how human speech communicated meaning. In 1951, he estimated that the English language had an 80% redundancy rate, allowing four out of five letters to be removed while retaining the meaning.
Shannon was a little harsh on English (more recent analyzes have revised this figure to 50%), but his basic theory has stood the test of time: languages convey meaning in different densities. And recording the raw speed of a language doesn’t take this fundamental factor into account.
Is there a limit to the amount of information our brain can process at once?
In 2019, researchers at the University of Lyon attempted to determine how the balance between speech rate and information density was averaged across 170 speakers reading set texts in 17 languages. They timed the time it took for participants to read this text (excluding long pauses).
The slowest speaker managed only 4.3 syllables per second, while the fastest spoke at 9.1 syllables per second, demonstrating that speaking speed varied considerably. What made things interesting was their calculation of the information density of each language.
They used Shannon’s original theory to calculate the conditional entropy of language syllables – essentially, how easy it is to guess what a syllable will be based on the syllable before it.
Vietnamese, for example, was one of the lowest-ranked languages in terms of speed, but each syllable encoded a lot of information. Vietnamese speakers had to pronounce fewer syllables to get their point across than, say, Spanish speakers.
Once the researchers combined the speed and information density of each language, they produced a new measure: information rate. Information rate determines the amount of information a language can transmit per second.
This information rate varied so little between languages that the researchers were able to settle on a “universal information rate” of 39 bits/second. They suspect this represents a rough limit to how quickly the human brain can understand speech, preventing language from going any faster.
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However, the study was not perfect. Erica Brozovsky, sociolinguist at Worcester Polytechnic Institute who hosts the PBS language show Other wordspointed out that the design could not capture the characteristics of everyday speech because all participants were reading a set text.
Brozovsky, who was not involved in the study, says Popular science“I don’t read things as naturally as I speak them, so the way I speak is going to be a lot faster and a lot more natural than when I read.”
Dan Dediu, a linguist at the University of Barcelona and co-author of the 2019 paper, agrees with Brozovsky and relates: Popular science that an ongoing study will seek to overcome this limitation by investigating a “much more natural use of language.”
This future work will also incorporate much more data from non-WEIRD (Western Educated, Industrialized, Wealthy, Democratic) languages to determine whether their information rate holds up at scale. Although the results are not official, Dediu shares that the unfinalized results of this work suggest that the information rate could be universal after all.
Although some languages group meaning into dense syllables while others spread it out, they all pass through the same human brain. There is so much to discover in the cultural and linguistic inventions that separate different languages, but how they vary in speed may not matter much. Science suggests that what we say is more important than how fast we say it.
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