The opening lines of The Analects, one of China's most famous historic texts, reads: "Is it not a pleasure to study and practice what you learn? Is it not good when friends visit from far off places?"

More than 2,000 years after it was written, the aphorisms of its author, the Chinese sage Confucius, might well be talking about China's rising language centers.

After a mere 12 years, China's Confucius Institutes are on 500 campuses and are now teaching Chinese language and culture to almost 2 million people.

Attached to foreign universities and named after the eponymous philosopher, the Confucius Institutes, overseen by the Office of Chinese Language Council International, or Hanban, are a network of not-for-profit Mandarin language-teaching schools and cultural centers for those who seek to learn about China.

The first institute opened its doors in Seoul in 2004. By the following year there were 33 in operation. As of today there are more than 500, spread across more than 134 countries and regions and on every continent except Antarctica.

Among the reasons for the institutes' current popularity, said Chu Hung-lam, director of Hong Kong's own Confucius Institute, is that China is genuinely interested in getting people to learn firsthand about its unique. often misunderstood, culture.

"China wants to tell and show herself and be understood," explained Chu, who is also head of the Chinese culture department at The Hong Kong Polytechnic University.

"That is a simple wish that many other peoples will share - and it makes good sense."

China is not alone when it comes to expanding cultural soft power. For years, countries have used their cultural cachet as a way to push a national tongue as a second language.

Among such respected cultural institutions are the likes of the British Council, The Japan Foundation, Germany's Goethe-Institut and France's Alliance Francaise.

The success of the Confucius Institutes did not happen overnight. Julia Gong, senior associate director of the Confucius Institute at The University of Melbourne, recalled that she only had four students when she started her first class in 2007. Today the institute is running at least three classes every weekday and has enrolled 976 students this year.

Gong said that the Melbourne institute is increasingly popular among Chinese-language learners. As well as offering non-credit Chinese courses to the general public, the institute also provides tailored language classes to a range of would-be Mandarin speakers, including undergraduates and university staff, businesspeople and government officials.

"With the increase in communication between Australia and China, in particular with the signing of the Free Trade Agreement between the two countries (in 2015), there has been more interest in learning Mandarin," Gong said.

With more Chinese travelers going to Australia, demand for language lessons in the tourism industry has grown too. During Chinese New Year, the Melbourne institute even held courses about the holiday to educate shop staff and tourism workers.

The China economy is driving global interest in Mandarin, placing the Confucius Institute network in an enviable position. Thanks to China's economic clout and expanding diplomatic links with the more than 60 countries included in the Belt and Road Initiative, there is little work needed to promote the language.

Proposed by President Xi Jinping in 2013, the initiative seeks to create a modern trade and infrastructure network across the ancient Silk Road routes.

Xu Tao, director of international cooperation and exchanges at the ministry of education, said during an interview with online news site China.cn in August: "We help people in countries along the Belt and Road learn Chinese, and these countries help us learn their languages."

Institutes in countries including Cambodia, Pakistan and Bangladesh have shown particular interest in blending language skills with future Belt and Road projects. For instance, one institute in Thailand, a country with 15 Confucius Institutes, has already begun teaching language classes related to railways ahead of plans to build a Thai-Chinese railway.

However, the reality is that the majority of Confucius Institutes are currently located in only a handful of countries. Over 100, for instance, are in the US, with more than two dozen in the United Kingdom - both countries with a long history of academic study of Chinese language and culture.

It is unlikely that China's economic power, on its own, can maintain a deep, widespread interest in learning a second language, said Molly Huang, who teaches Mandarin in South China's Guangdong province and Hong Kong. Instead, she said that first and foremost, language is entwined with culture.

Gong of Melbourne's Confucius Institute agrees, stressing that the teaching of language and culture cannot be separated. "Culture is a very big concept," she said.

The Confucius Institutes' growing influence at foreign universities has not been without controversy, however. They have been accused of being opaque, too political, or sometimes even not political enough.

"Since they bring funding, trained teachers, organized programs, and textbooks, (Confucius Institutes) have been welcomed with open arms by some university administrators," said Robert Bauer, an honorary professor of Chinese linguistics at the University of Hong Kong.

"At the same time, however, I am aware that awkward situations have arisen over political issues at some schools, and their Confucius Institutes were asked to close and leave."

Indeed, some Confucius Institutes have suffered such a fate in countries including Canada, Sweden and the US.

In other cases, the institutes simply have not got off the ground. In Japan, none of the elite public universities have agreed to allow a Confucius Institute on campus, though almost a dozen private universities have done so.

Despite these hiccups, Hanban has a clear plan for its institutes. By 2020, it aims to have more than 1,000 open worldwide.