The second president of the United States, John Adams, predicted in 1780 that "English will be the most respectable language in the world and the most universally read and spoken in the next century, if not before the end of this one." It is destined "in the next and succeeding centuries to be more generally the language of the world than Latin was in the last or French is in the present age."
It was a bold prediction, for at that time there were only about 13 million English-speakers in the world, almost all of them living in Britain or on the eastern seaboard of North America. They were barely one per cent of the world's population, and almost nobody except the Welsh and the Irish bothered to learn English as a second language. So how is Adams' prediction doing now?
Well, it took a little longer than he thought, but last week one of the most respected universities in Italy, the Politecnico di Milano, announced that from 2014, all of its courses would be taught in English.
There was a predictable wave of outrage all across the country, but the university's rector, Giovanni Azzoni, simply replied: "We strongly believe our classes should be international classes, and the only way to have international classes is to use the English language. Universities are in a more competitive world. If you want to stay with the other global universities, you have no other choice."
The university is not doing this to attract foreign students. It is doing it mainly for its own students who speak Italian as a first language, but must make their living in a global economy where the players come from everywhere -- and they all speak English as a lingua franca.
Many other European universities, especially in Germany, the Low Countries and Scandinavia, have taken the same decision, and the phenomenon is now spreading to Asia. There is a huge shift underway, and it has become extremely rare to meet a scientific researcher or international businessperson who cannot speak fluent English. How else would Peruvians communicate with Chinese?
But wait a minute. Peruvians speak Spanish, the world's second-biggest language, and Chinese has the largest number of native speakers of any language. Why don't they just learn each other's languages?
Because neither language is much use for talking to anybody else. Chinese won't get you very far in Europe, Africa or the Americas -- or, indeed, in most of Asia. The same goes for Spanish almost anywhere outside Latin America.
Since few people have the time to learn more than one or two foreign languages, we need a single lingua franca everybody can use with everybody else.
The choice has fallen on English, not because it is more beautiful or more expressive, but just because it is already more widespread than any of the other potential candidates.
Mandarin Chinese has been the biggest language by number of speakers for at least the last 1,000 years and is now used by close to one billion people, but it has never spread beyond China in any significant way. Spanish, like English, has grown explosively in the past two centuries: Each now has more than 400 million speakers. But Spanish remains essentially confined to Central and South America and Spain, while English is everywhere.
There is a major power that uses English in every continent except South America: the U.S. in North America, the United Kingdom in Europe, South Africa in Africa, India in Asia, and of course Australia (where the entire continent speaks it). All of that is due to the British empire, which once ruled one-quarter of the world's people. For the same reason, there are several dozen other countries where English is an official language.
Of course, the British empire went into a steep decline almost a century ago, but the superpower that took Britain's place was the United States, another English-speaking country.
After another century during which everybody dealing in international business and diplomacy -- indeed, any independent traveller who went very far from home -- simply had to learn English, the die was cast. English had become the first worldwide lingua franca.
There have been few languages in world history that were spoken by more people as a second language than as a first; English has had that distinction for several decades already. Never before has any language had more people learning it in a given year than it has native speakers; English has probably now broken that record as well.
Most of those learners will never become fully fluent in English, but over the years some hundreds of millions will, including the entire global elite. And the amount of effort that is being invested in learning English is so great it virtually guarantees this reality will persist for generations to come.
No other language is threatened by this predominance of English.
Italians are not going to stop speaking Italian to one another, even if they have attended the Politecnico di Milano, and no force on Earth could stop the Chinese or the Arabs from speaking their own language among themselves. But they will all speak English to foreigners.
Gwynne Dyer is a London-based independent journalist whose articles are published in 45 countries.