How many languages are spoken by the world’s people?

Try seven thousand. That’s an impressive number— at least until you discover that many are on the way out.

In the next hundred years, fully half of these languages will have died. What, if anything, can we do about it? Should we even care?

These are questions asked by linguists like Catherine McKenna, a professor of  Celtic studies at Harvard. I recently had the good fortune of hearing her deliver a remarkable lecture about endangered languages.

In later life, subjects like this continue to fascinate me. Old age need never be a  barrier to learning about the larger world.

For linguistic perspective, it helps to realize that a few regions of the world are home to many of the languages. Papua New Guinea alone has 847 native languages, at least for the time being.

And the people of Indonesia currently speak more than 600.

Among the declining tongues, 500 have fewer than 100 speakers. It is difficult to imagine the sadness of those who realize that the language of their ancestors will soon cease to exist.

As a Scottish poet once said, in words beloved by Professor McKenna: “It is a terrible thing to watch the language in which you dream die and disappear from the earth.”

Even when a language is spoken by 200,000 people, is it safe from extinction? That’s the number of people who speak Breton, a Celtic language rooted for many centuries in northwestern France.

The Welsh language is a cousin of Breton. Decades ago, I spent an academic year living in northern Wales, but only rarely did I hear the local language.

The modern world is not friendly to linguistic diversity. Isolated settlements are no longer beyond the reach of modern technology. Young people refuse to speak in old-fashioned ways. Television tends to drown out the languages of the minority.

Some people do not regret the disappearance of languages. They even think that having fewer will contribute to unity and world peace.

But for Professor McKenna, and for many other scholars, each language is invaluable. A given language may even convey specialized knowledge not otherwise available.

She cites the discovery of an enzyme that was recognized and transmitted by a Samoan language. This discovery has led to a drug proven effective in treating HIV.

Broader cultural value comes in stories, poems, and other literature passed down by native populations. When we lose hold of such traditions, we deprive ourselves of cultural perspective.

And these perspectives may be very subtle. We should never conclude that a simple life produces a simplified way of speaking. Every language has its own complexities that challenge those who want to learn them.

Language itself, in whatever form, is surely one of the human family’s great treasures. It ranks as a kind of miracle that we can communicate with other people and turn this communication into art.

The scholar who inspired this column left her audience with some suggestions for actions to save threatened languages.

Colonial powers frequently destroyed native languages by banishing them from schools and forbidding children from speaking them. Today’s decision-makers need to cultivate respect for speakers of native languages, the bearers of a treasure that is becoming increasingly rare.

Currently, eight languages of the world have over 100 million speakers each. Some of them—English, Arabic, Mandarin Chinese, Spanish are examples—have huge numbers, making them likely to overwhelm the rest.

But it would be tragic to see the others disappear. They help form the beauty and variety of the human family.