BOGOTÁ — I had an opportunity in recent weeks to spend time on not just one, but two islands.

The first was La Palma, the westernmost island of the Canaries — the one that's closest to the Americas, in other words. The Spanish spoken there sounds more Venezuelan than Castillian, while the vegetation (bananas, sugar cane and bougainvilleas) seems more Caribbean than anything you'd find in Spain.

Perhaps the most extraordinary thing about the island is the presence of one of the world's most important observatories. The facility, built at 2,400 meters above sea level atop a dormant volcano formed 20 million years ago, the Roque de los Muchachos, holds the world's biggest telescope, the Gran Telescopio Canarias.

What isolate us most thoroughly, rather, are mountains.

To perceive the very few photons or light particles reaching us from the past (that is the rays of remote explosions that happened thousands of millions of years ago, when the sun and the earth were not yet formed), one needs the stillest, most transparent atmosphere and considerable darkness. For that reason public lighting in La Palma is dimmed to the point of elimination, and the night really does appear as it should. The greater the darkness, the more nocturnal the night.

In La Palma, it occurred to me for the first time that islands are not, in fact, insular. What isolate us most thoroughly, rather, are mountains. Christopher Columbus, we were taught, left Huelva, Spain on Aug. 3, 1492. Considering it more carefully, he abandoned Spanish territory definitively on Sept. 6, specifically from another of the Canary islands, La Gomera. That was the last supply point where he loaded water and food and mended the helm and sails of his ship, La Pinta.

La Palma, Spain — Photo: Hilthart Pedersen

No, neither the sea nor rivers isolate as mountains do. There is trade on islands. People of different races and cultures dock at ports, and islands have sent fleets to conquer the world. And if that was the case for the Canaries, it has been even more so for the other island I visited of late, Great Britain.

These green isles created the last great empire that merits the name. And it is for an absurd nostalgia for that imperial past that the United Kingdom now wants to leave Europe. They mistakenly think that if they go back to being an island, their greatness will return. The idea is stated with ridiculous Trumpian grandiloquence when Prime Minister Boris Johnson vows to "make the UK great again!"

Great Britain is the clearest example of how an island is anything but isolated. If there's one thing that's truly global — something that's gone viral worldwide — it is England's language and culture. English is the most widely disseminated first language, and as a second language practically all of us have a jab at it! Cuba, Crete, Japan and Indonesia are other examples of how islands integrate with the territory around them, or conquer, influence and dominate it.

Great Britain is the clearest example of how an island is anything but isolated.

Spending time on islands that either communicate with (La Palma) or come to dominate the world (Great Britain), I realized that the people who are truly isolated are those of living in mountains. Tibet is an isolated land. So is Bolivia, Switzerland and Paraguay.

One of our presidents, Alfonso López Michelsen, rightly described Colombia as "the Tibet of South America." It is a parochial country, closed to immigration, trade and ideas, with a capital clinging to the Andes and so far from everything it appears distant from itself.

If only "water surrounded us on all sides," as the Cuban writer Leonardo Padura said of his island. Our only obstacle, in that case, would be the sea, and wouldn't be limited by the little enclosure of our minds and the idiocy of extreme self-regard.

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