When I was 18 years of age, I had occasion to visit the Gare de l'Est in Paris. I don't even remember why I was there, but I remember a vivid moment of the experience. I gazed on the line of trains waiting to depart from their platforms: the destination boards read "Varsovie" (Warsaw), "Moscou" (Moscow), "Istanbul" and "Pekin". This was what it meant to be a continent. You could take a train all the way to Russia, or Turkey, or China, all overland.
An epiphany, surely, for a person coming from an island. An island is so different from a continent - obvious, but seldom reflected on. An island is a place apart - defined in the Oxford Dictionary as not only surrounded by water, but "a thing that is isolated, detached". The very word "isolate" derives from late Latin "insula", which is also cognate with insular.
To be an islander has its benefits: Gavin Francis, the Scottish doctor and travel writer, who is obsessed with islands, believes that islands are therapeutic, because their sense of "containment" can bring peace of mind. "Islands help to recalibrate what matters."
But the island and the islander can become isolated, in a cut-off sense. And over the last six months, there seems a perceptible drift in Ireland to revert to an attitude of isolation. Foreign travel has collapsed. The aviation industry - so crucial to an island - is in a parlous state and is often condemned for struggling to keep going "just for profit". Within the island of Ireland itself, people are urged to "self-isolate" - to become islands within themselves.
New Zealand, which cut itself off from the rest of the world to halt the spread of Covid-19, has been cited as an admirable model, although New Zealand is a more remote Pacific island, which has no international border on its territory, has fewer trade connections and no treaty with a continent, as Ireland has with the EU.
There is an unconscious, maybe primitive, urge within islanders to contain themselves, not to let "outsiders" into their secluded island world.
Ireland is an archipelago of islands - with at least 80 around the coast, of which 20 are inhabited, so the presence of islands abounds. Visitors may be made welcome, but there is suspicion, too, of outsiders.
Visitors to Ireland have been described as carriers of disease, "spreaders", a nefarious presence. Disapproval has been voiced that anyone at all should be landing at Irish airports during this summer of the coronavirus.
Fear of a pandemic is understandable and health precautions are sensible, but what of the psychological impact of sealing ourselves off from the outside world?
Some have felt a sense of cultural suffocation at not being able to get up and go, to emerge from the island state, to escape the "staycation". People can connect globally through modern media, but it is never quite the same as being there, as having the experience.
Charles de Gaulle excluded Britain from what was then the European Economic Community, calling the island of Britain "insulaire". Descriptively, he was correct: island natives are of the "insula", though they may see the foreigners as the isolated ones. "The Continent is isolated by fog," went a BBC weather forecast in 1938.
For more than two centuries, until 1868, Japan was separated from the outside world and it was a period of peace and serenity. They cursed the Portuguese for disturbing their island tranquillity. Japan, too, is "insulaire" - content with its island status, encompassing 6,000 islands.
There are, I think, some people in Ireland today who would like to emulate 17th-century Japan. Gavin Francis, in his book Island Dreams, points out that islands have always been places of containment and thus ideal for imprisonment: Alcatraz, Robben Island, Chateau d'If. And of contained exile: Elba, St Helena.
The fascination of being marooned on an island was captured by Daniel Defoe with the legend of Robinson Crusoe, based on the experience of Alexander Selkirk. Defoe wrote about the further adventures of Robinson Crusoe, but readers were only interested in his island story.
Ireland's geographical insularity has always been accompanied by the psychological need to connect with the world beyond the island. Sometimes that was forced, through economic emigration, but often it was led by a natural curiosity: the Irish diaspora is the evidence of that global inter-connectedness. Brendan the Navigator was an early model.
The islander loves the island, but there is also the urge to be connected, to be part of a bigger whole. As John Donne wrote in 1624: "No man is an island, entire of itself/Every man is a piece of the continent, a part of the main."
The child psychoanalyst Donald Winnicott believed that the island experience of isolation brought a benefit: he thought that periods of waiting in isolation are periods of healing. "Waiting and waiting and waiting," is what he recommended.
That just about describes the state we're in.