Milton Glaser emerges from his studio holding a button badge which would be of a life-affirming verdant colour if it weren't horribly tarnished by a cloudy black stain which almost eclipses the lush green altogether.
The image is unsettling and imperfect. It lacks the purity, though not the simplicity, that one associates with America's best-known graphic artist and his most famous work, such as the 'I Love NY' design, which has been appropriated into an international expression of affection.
He wants the world to wear his climate-change button badges, just as they have embraced the heart symbol that he sketched in red pencil crayon on a torn envelope in the back of a New York taxi on his way to work at this same studio 37 years ago. On the short walk from the New York subway station to his workplace on the Eastside of Midtown Manhattan, I pass three shops which appear to be exclusively dedicated to selling goods carrying the heart logo, which continues to earn Glaser's original client, New York State (not, as many assume, the City) $30m a year.
Glaser is 84 and when he abandons his patient reminiscing on a remarkable career to speak of his button-badge project, a note of urgency comes into his voice. "I have started a campaign that we hope becomes global called 'It's Not Warming It's Dying'. The idea is to have everybody wear this button all over the world as acknowledgement of what's going on." He embraces Buddhist philosophy which suggests "acknowledging" a problem is better than attempting action and exacerbating it.
But he declines to describe the badge in his own words (his studio hasn't yet released the image, either). "If it's not obvious, it doesn't work." And when asked to expand on his motives for launching a campaign that will include a website where the badges can be ordered, he responds dryly: "The fact that the world is coming to an end... and that the most important event in human history is not acknowledged."
Glaser's work remains in the public eye – he made the psychedelic promotional art for the seventh and latest series of the cult television show Mad Men. Its creator, Matthew Weiner, was a fan of the design guru's output. For Mad Men, Glaser has drawn on the Art Nouveau-inspired poster he made for Bob Dylan's Greatest Hits in 1966, showing the singer with kaleidoscopic hair. The result is a silhouette of a seated Don Draper, arm outstretched with a cigarette between his fingers, gazing on a scene of Sixties cornucopia.
Part of the reason Glaser took the job was that, "to be truthful, I was apprehensive about whether or not I could still do it".
Although he has said he recognises the show's depiction of a time when his work was admired on Madison Avenue, he clearly has no desire to be seen as an ad-man. "I don't like advertising and I don't like the values of advertising very much," he says. "I just realised that the idea of persuading people to do things against their own interests was not where I wanted to be in life. Since that occurs on a regular basis in advertising, you have to be cautious about entering into the conspiracy."
Milton Glaser was born in the South Bronx to Hungarian immigrants in 1929. His father owned a dry-cleaning business and his mother was a housewife. The neighbourhood, which contained some of New York's first co-operative apartment buildings, was fiercely left-wing and anti-capitalist, and he has retained these instincts throughout his life.
'Art is Work', the slogan in the window above the door of the Beaux-Arts townhouse where he has been based since 1965, is not a tribute to money-making graft but a plea for the public to claim art for themselves. "My intention was to not remove art as a separate activity but to integrate it into the everyday life of everybody."
His current work involves "ceramics, fabrics, watches". He has downscaled his operation to two designers and an assistant. "I'm not interested in using the studio as essentially a financial mechanism, I'm interested in seeing what opportunities for inventing things the studio will serve."
He works from a desk beneath pinned-up images of floral-printed horse heads and Eastern art. "I don't ever touch a computer," he says, but he is happy for colleagues to deploy this "very subversive instrument" according to his instructions, in order to speed up the working process. "The computer enables you to eliminate an enormous amount of waiting time."
Glaser attended the Cooper Union for the Advancement of Science and Art in New York's East Village. In 1954, Cooper graduates Seymour Chwast, Edward Sorrel, Reynold Ruffins and Glaser established Push Pin Studios, which was to become a byword in graphic design for several decades.
Much of the important work in Glaser's career has been the result of collaboration with a key partner. In 1968, he and Clay Felker set up New York magazine, still one of America's finest periodicals. Although the "weights have changed" in the familiar masthead which Glaser designed, it has recently "gone back to looking more like it was when we launched it".
He is not directly involved with New York any more, but he is pleased it has "regained its footing" and is more recognisably the publication which he and Felker created to represent the city on which Glaser has left a stamp like few other of its natives. "The great thing about New York is it's not a single place. New York has a kind of mind set," he says proudly. "Anywhere you are in Paris, you know you are in Paris. But if you are in New York, you turn a corner and you are some place else. It's so complex and has so many attributes that you have to invent it."
He thrives on this potential for surprise. "The nature of being in this world and the thing I most want to retain, is the capacity for astonishment. I still feel it. I wake up every day with this sense that I'm going to be astonished by something."
Glaser acknowledges that the imprint he has made fulfils a common human instinct to leave an enduring legacy. "I think everybody feels the same way, they would like to think their life added up to something that went beyond their own desire and needs," he says. "I like the idea that something I'd made endures, for a while at least."
But when 9/11 happened, he lost something more than the work he had created at the World Trade Centre. He recalls how he was sitting at the same wooden table where he is now (and where he founded New York with Felker), looking out through the window at a pall of smoke above the city skyline.
Along with the massive loss of life in the tragedy, the destruction of the Twin Towers also meant the end of the famous and spectacular 'Windows on the World' 107th floor restaurant, for which Glaser's studio designed everything from the lighting fixtures to the menus. He was less concerned by the demise of his creation than by the breaking of a personal bond with the great restaurateur Joe Baum (who died in 1998), with whom he conceived the project.
"What was more important to me than the project was my relationship to him, and I find that has generally been true in all my work. Almost everything decent that I have done has depended on a specific relationship with a specific person that has created an environment and the opportunity to do good work."
An unlikely rapport with the right-wing British financier Sir James Goldsmith, led to one of Glaser's biggest projects, designing the Grand Union supermarket chain. "I never thought I could feel well-intended towards somebody who had such reprehensible and reactionary views of things. But we had wonderful talks together and we would have dinner frequently and he was very open-minded to all the projects I was working on."
He struck up another great rapport with Steve Hindy, a former Associated Press correspondent who founded the Brooklyn Brewery in one of New York's more deprived neighbourhoods in 1984, and persuaded Glaser to do the graphics. Because the founders had little money, Glaser "took part of my fee in equity" and the brewery guides say he still occasionally claims his entitlement to free beer. The logo he drew was based on the letter 'B' of the Brooklyn Dodgers, an initial which disappeared when the baseball team abandoned the borough and moved to Los Angeles in 1958. The success of the brewery has ensured Glaser's design has become a symbol of Brooklyn's recent economic renaissance.
New York itself was in a desperate condition in 1977, when Glaser made that momentous taxi journey to his 32nd Street base. He had already submitted a design to the client, the Assistant Commissioner of Commerce, Bill Doyle, but now rang him up to say, "I have something better". His original "all typographical" pattern "would have disappeared in a month," he says.
With so many people departing the crime-ridden city, the heart design struck a chord with those who didn't want to leave. "People were moving out and the people who were here wanted to be able to say 'I Love New York'. It was a real, deeply-felt desire and there were so few opportunities that any of us have to express the deepest things we feel."
True to his anti-capitalist roots, he is discomfited by the way the design has been commercialised. "They have decided that it is no longer a symbolic object to generate affection, but a potential money-making icon, so they have stores that sell nothing but 'I ∫ NY' products, all of which I find makes me nervous and unhappy."
But after 9/11 he made a new version, 'I ∫ NY More Than Ever', and his mechanism for expressing affection "won't die," he says. "To last from '77 to now, without showing a lot of loss of energy, is quite interesting." Later, he notes the profundity of the statement: "Everything is interesting if you pay attention to it".
He is talking above the shouting of children playing in the public schoolyard that adjoins his studio. For the past 55 years, Glaser has been teaching, conscious of the role in his career of the Italian painter Giorgio Morandi, under whom he studied in Bologna during a Fulbright Fellowship before starting with Push Pin. He tells design students that they must learn to draw – or be dependent on the work of others.
He is conscious that younger generations are increasingly wary of all messaging. "You have a very cynical audience that recognises ... that they have been persuaded by others to do things they would not necessarily choose themselves. People say, 'Why should I believe that, I've been lied to before?'. There's a deep sense of betrayal in all cultures now; betrayal by the powerful, by the controlling classes. You're seeing it all over the world."
Hopefully, the cynicism will not dissuade them from wearing his badges.
Because Glaser is neither an ad-man nor even a campaigner, he says.
"I just think it's part of being a good citizen. That's all".