If one was lucky enough to have lived in Paris while young, wrote Ernest Hemingway, the city would remain with you for the rest of your life. Humphrey Bogart echoed the sentiment with that classic movie line from the closing frames of Casablanca. "We'll always have Paris," Rick, his character, tells the woman he will never see again. And even Art Buchwald, the humour columnist, weighed in, titling his charming memoir I'll Always Have Paris.
As it happens, friends with whom I was recently reunited after half-a-century lived in Paris when we were young, fell in love with the city, and, being what it was, inevitably fell in love with someplace we never saw again.
This was our Paris of the 1960s, where we could often find ourselves alone with Mona Lisa's smile; the quais along the Seine River were dedicated to strollers and not-too-speeding vehicles; and the Eiffel Tower could be viewed without peering through a haze that sometimes exceeds the toxic pollution levels of Beijing and Delhi.
The first McDonald's on the Champs-Elysees was still a decade away, the favoured fast-food venue being Les Halles, the pulsating, centuries-old central market razed in 1971 to be substituted by an underground shopping mall. And when ordering its signature onion soup among the bustling butchers and fish mongers after a hard night out in the Latin Quarter, we actually had to know our French or risk a waiter's arrogant Gallic shrug.
And lest one forget, as even many among France's young generation have, Paris in the 60s witnessed an eruption of creativity -- highbrow, pop and political -- the likes of which has not been remotely equalled in the City of Light since.
"We lived in a special time. We were very privileged," said schoolmate Nanette Petiprin Marranca, a vivacious woman who has retained her superb French.
We studied at the American School of Paris, then shoehorned into the music pavilion of Madame du Barry, an 18th-century miniature as graceful as a minuet. Set on a forested ridge above the Seine River, its byways and bowers were said to be haunted by Madame, the glamorous No.1 mistress of Louis XV, whose party lifestyle was cut short by the Revolution's guillotine.
The reunion was organised at our alma mater's now sprawling, sleekly modern campus, catering to more than 700 students who are ringed by barbed wire and guarded by an antiterrorist unit. My graduating-classmates numbered 27, just one measure of how much Paris has upsized since our time.
Long a frontrunner, Paris perennially ranks as the world's No.1 tourist destination in the most visited country on earth (100 million projected for 2020). Despite a series of bloody terrorist attacks last year, Paris still attracted a record 23.6 million, with Americans leading the influx and the Chinese in the fourth spot and accelerating fast. The municipal tourism office didn't have any statistics for the 1960s but noted that about 5.8 million visitors arrived in all of France in 1961.

Paris, of course, has rarely been tourist-free or immune to earlier versions of globalisation, and the 1960s were no exception. Succumbing both to its allure as well as our youthful snobbery, we desperately tried to fit into la vie Parisienne, the more desperate and industrious by rigorous study of French. My sister and I would drag along our elegant cocker spaniel Hermes wherever possible in the canine-friendly city, hoping we would thereby not be confused with a category known as "the ugly-American tourist".
Some of the romantics among us half fantasised that our Paris would remain frozen in time, immune to the blights which few cities the world over have evaded. I am sure that some decades from now another generation, in their autumnal musings, will remember their Paris with a fondness equal to ours, just like some in the 1960s harked back to the 1920s as the city's golden era, a notion charmingly depicted in Woody Allen's 2011 film Midnight In Paris.
And today that generation accepts Paris as the new normal, perhaps not making any comparisons with the past and reckoning that the draws of its abiding glories still outweigh the negatives. Like having to book online to view Leonardo da Vinci's Mona Lisa, which my classmate Ken Lally had to do, and then jostling for a glimpse through clutches of phone-camera-wielding visitors to the Louvre Museum (8.1 million last year). Or standing for as long as three hours in "monstrous queues" (a quote from complaining staff) for a glide up that stalwart icon, the Eiffel Tower (and site of one of our senior proms).
Many graduates from the classes of the first half of the 1960s went on to lead successful and fulfilling lives. A number of us, the baby boomer generation now in its 70s, attained high positions as company CEOs, prominent professionals and academics. Jimmy Jones (aka Gen James Logan Jones Jr) became the Supreme Allied Commander in Europe and US national-security adviser. Most lived their post-school years in the United States. A few never left France. But all I know never severed their special bonds with Paris.
Some at our reunion took a more benign, nuanced view of today's Paris than I did, returning to an urbanscape the historic core of which had remained so much more intact than most -- and encountering a spirit with which they could still connect.
"In my mind that special Parisian energy has been alive since before the French Revolution. I have no problem with Paris," remarked Peggy Leong, formerly a research biologist and still a champion swimmer from California. "From my chair at the Cafe Les Deux Magots on the Boulevard St Germain, I can't really notice much change over the years," said Robert Dean-Turner, a retired engineer turned prolific painter of European landscapes at this haunt of Hemingway, Pablo Picasso and a roll call of other luminaries past.
Perhaps I was more sensitised to change, having as a foreign correspondent on several continents witnessed irrevocable loss over incredibly short periods of material and intangible cultures and unique atmospheres. When it comes to Paris, I must also confess to a touch of selfishness: even on a very modest allowance from my parents I could in the 1960s afford a ticket to the opera, a night at the legendary Cave de la Huchette jazz club, and didn't even think twice about coffee with friends at the Cafe George V, each of which would today considerably lighten even adult pocketbooks.
My own backstory aside, a consensus among my friends was that Paris, for better and worse, had become less Parisian, less French. It had also lost some of both its grit and its elegance, and perhaps some of its creative juices.
Through the prism of nostalgia, even the grit and grime glowed, like the now rather rare whiff of those truly awful Gitane and Gauloise cigarettes or the soot-covered buildings along the boulevards long since scrubbed and gleaming. Or, as Peter Dupret remembered, "the old Peugeots with heavy clacking diesel engines like those which woke you in the wee morning hours in Paris' quiet resonating streets".
Peter, a retired aviation executive, lived for a time on the rue Pierre Charron with his parents (and remembered by his classmates as very handsome). When surveying the street and its neighbourhood, he was disappointed that the streetside pissoires had vanished, those stinky but very handy and quirky public urinals (in fact only a single token one survives in all Paris, down from 329 in the mid-1960s). He did, however, locate several places advertised as "French Restaurant" as well as a Starbucks, Burger King and McDonald's -- hardly a surprise since last year the hamburger dethroned the jambon-beurre baguette as France's favourite sandwich: 1.46 billion buns of Americana to 1.22 billion baguettes filled with sliced ham.
"Sound like the mall in Anytown, USA, today?" Peter said, but added a graceful bow to change: "We have now aged, and so has the quarter."
Walking again along the nearby Champs-Élysées, Peggy missed "the French fashionistas strolling the avenue in their high-heeled shoes and dressed to the nines, whom we used to watch from the sidewalk cafes, who are now replaced by hordes of jeans-clad tourists". Laura Lopez, whose father opened the first embassy of the Philippines in France, took a stroll down the Rue de Rivoli, past once-seductive stores now selling key chains, exuding "a commercialisation that seems un-French".
"But this is probably part of the global trend," she said. "Paris has changed because the rest of the world has."
However, Laura, soft-spoken, petite and herself a former high-powered diplomat, felt at ease with another, more meaningful transformation: one-fourth of Parisians have moved to the city after they were born and some 40% of its children have one parent who arrived as a first-generation immigrant. Paris had become one of the most, if not the most, diverse city in Europe, ushering in new attitudes, new vibes, new colour.
Factoring out our unabashed nostalgia, a case can otherwise be made that since the 1960s Paris has nonetheless veered more toward a museum than a hothouse of creativity.
Although certainly never invited to join them at the Cafe Les Deux Magots to discuss the Big Questions, the likes of novelist Albert Camus, existential philosopher Jean-Paul Sartre and feminist Simon de Beauvoir radiated atmospherics that percolated down to our level. We did frequent cinemas showing now-time-tested films by Francois Truffaut, Alain Renais and other directors of the French New Wave, then at its innovative crest. And may have viewed less rarefied fare starring the sex symbol Brigitte Bardot.
The quintessential French songstress Edith Piaf, racked by pain from cancer and barely able to stand, gave her last concert in 1963. Among a panoply of younger superstars, Johnny Hallyday was in his heyday (when the rocker died last year, a million Parisians took to the streets as the funeral procession passed).
And on the Left Bank students were generating new ideas for a movement that would climax in the great revolt of May 1968, a watershed year which propelled France out of the postwar era of sacrifice and control toward a more open political and social order.
Indeed we did live in Paris at a special time when, as Robert, a bon vivant of substantial girth, asserted: "One ate real food, real culture -- not rechauffage" (something re-heated).
The high point of our reunion was a return to our old school, the pavilion currently a venue for weddings and conferences and an occasional backdrop for Dior perfume ads.
Its ground floor was still graced with gilded ceilings, cherubs in marble, paintings of pastoral scenes and the bust of a rather busty Madame du Barry. We were stepping into an 18th century come to life, and our old school days.
But up the circular staircase, on the second floor, our quaint classrooms had been converted into seminar rooms of monochromatic colours and stocked with hi-tech paraphernalia. "We're in sanitised, corporate America," Robert remarked. Then he turned and explained to a wide-eyed yet somewhat dubious youngster in our party: "You see, we were princes and princesses once. We came from this chateau."
On my last night in Paris, the Place de la Contrescarpe was bursting at the seams. Locals, foreigners and students from the surrounding Latin Quarter jammed its outdoor cafes and bars. Under a mellow, setting sun and amid a veritable chorus of joie de vivre, obliging waiters serpentined around tables, aperitifs aloft on tottering trays. "Paris can always bring you back," said Beverly Brandt, a retired business executive, greying but still willowy, and my first love. "Her sounds, smells, tastes and visual treats provide a unique, altered state that, if you let it, can last a lifetime."
The scene at the square that evening might have been a set for Act 2 of La Boheme, the tale of 19th-century Bohemian life in the Latin Quarter. To me, it brought back the touching final lines of the book upon which Puccini's opera is based.
If I may translate and paraphrase:
Our youth lies buried at the bottom of old calendars, and only by stirring the embers of its joyful days can we recover la clef des paradis perdus -- the key to a paradise lost.
A longtime bureau chief of the Associated Press in Thailand, Denis now lives in the hills near Chiang Mai.