Soccer star David Beckham shows his tattoo in response to students' request at Peking University during his visit in Beijing on March 24, 2013. The tattoo in Chinese characters reads, “Life and death are determined by fate, rank and riches decreed by heaven.” (Reuters)

Twitter's decision this week to test 280-character tweets is a nod to a fundamental linguistic truth: Some written languages are more concise than others.

The social media company's engineers noticed that people writing tweets in English were far more likely to hit the 140-character limit than people writing in, say, Japanese. “This is because in languages like Japanese, Korean, and Chinese you can convey about double the amount of information in one character as you can in many other languages, like English, Spanish, Portuguese, or French,” the company wrote in announcing the change.

For a clear illustration of this, we can look at the amount of characters it takes to render the same text in different languages. For our test case, we'll use Article 1 of the Universal Declaration of Human Rights, which is handy because the United Nations has translated this document into hundreds of languages. For this reason, the Unicode Consortium, which sets standards for how computers render text, uses the declaration as a benchmark reference.

In English, Article 1 reads as follows: “All human beings are born free and equal in dignity and rights. They are endowed with reason and conscience and should act towards one another in a spirit of brotherhood.” That adds up to 170 characters, including spaces and periods — too big to fit in a tweet.

Other languages require more characters to render the same text. In Spanish, it's 171, French requires 186, and Greek needs a whopping 196 characters.

On the other hand, you can convey the same ideas with far fewer characters in a number of other languages. You can fit Article 1 in a tweet if you're writing in Czech, which requires 138 characters. Hebrew needs only 126.

But Japanese, Korean and Chinese are in a class of their own when it comes to expressing yourself concisely in writing. In Japanese and Korean, you need only 87 characters to write Article 1, while Chinese requires just 43.

The reason? Chinese characters — like those used in Japanese writing — are logograms, representing a full word. Characters in English and most other written languages, by contrast, represent sounds.

As far as your computer is concerned, when it's displaying text, it doesn't matter if a given character is a simple Roman letter like “I” or a relatively complex Chinese character like “我” (meaning me/I) — they're each one character. So the word “elephant” takes up eight characters in English but just one character (象) in Chinese.

In other words, you can fit 140 elephants in a Chinese-language tweet but just 17 in an English one.

That's the situation Twitter is trying to address with the character change. Notably, Chinese, Japanese and Korean users will still be restricted to 140 characters, the thinking being that they already have enough space to express themselves.

Whether more characters will improve the Twitter experience for everyone else remains an open question.