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Lee Kuan Yew, who died on Monday at the age of 91, is famed as the man who turned Singapore from a small port into a global trading hub. But he also insisted on tidiness and good behaviour - and personified the country's ban on chewing gum. What was it about gum he so disliked?

For a while after the gum ban was introduced in 1992 it was all foreign journalists wanted to talk about, Lee Kuan Yew complained later, in conversation with US writer Tom Plate. That and caning, as a form of punishment.

The ban remains one of the best-known aspects of life in Singapore, along with the country's laws against litter, graffiti, jaywalking, spitting, expelling "mucus from the nose" and urinating anywhere but in a toilet. (If it's a public toilet, you are legally required to flush it.)

When Singapore became independent in 1965 it was a tiny country with few resources, so Lee, the country's first prime minister, hatched a survival plan. This hinged on making the city state a "first-world oasis in a third-world region".

Before very long, Singapore was outstripping other developed countries in terms of its cleanliness, clipped lawns, and efficient transport system. The Cambridge-educated Lee, it seems, was aiming for perfection.

Image copyright Reuters

"For many years as a visiting columnist, I too chewed over the puzzle of the chewing gum conundrum, but came to understand that the tendency to stick the remains of the gum in every which place was viewed by the authorities as a palpable attack on Singapore's ambition to be perfect," writes Plate, in his book Giants of Asia: Conversations with Lee Kuan Yew.

If you can't think because you can't chew, try a banana Lee Kuan Yew

"That is, it was anti-utopian. It was gumming up the works. As far as LKY and his team were concerned, the yucky habit, commonplace in the old days, was a palpable enemy of progress. The way to edge forward toward utopia was simple: simply outlaw chewing gum."

By the time the gum ban was implemented, Lee had completed 31 years as prime minister, and had become "senior minister", a big power behind the scenes.

"We were called a nanny state," he told the BBC's Peter Day in 2000. "But the result is that we are today better behaved and we live in a more agreeable place than 30 years ago."

At that time, Lee was pushing for a "new burst of creativity in business" and Day "hesitantly" suggested that chewing gum stuck to the pavements might be a sign that the desired new spirit of creativity had arrived.

Lee grimaced.

"Putting chewing gum on our subway train doors so they don't open, I don't call that creativity. I call that mischief-making," Lee replied. "If you can't think because you can't chew, try a banana."

Lee felt there was a public policy solution to everything, Plate says, even that gum on the pavement, or the doors of the "mass rapid transit" trains. "He was what I call a pragmatic utopian," Plate says. "He woke up in the morning and said, 'How can I make it better today?'"

Image copyright AFP Image caption Gum used to hinder the working of the MRT doors

Gum is, anyway, "largely legally chewable" nowadays, Plate says.

We Singaporeans, describe Singapore as a 'fine city' Eugene Tan, Singapore Management University

It has always been legal to bring small amounts into the country for one's own use.

Since 2004 - as a result of the US-Singapore Free Trade Agreement - pharmacists and dentists have also been allowed to sell "therapeutic" gum, to customers with a medical prescription. This includes standard sugar-free gum.

You'd still face a steep fine for spitting out the chewed gum and leaving it as litter.

"We joke about these policies... we Singaporeans describe Singapore as a 'fine city' - a tongue-in-cheek reference to the many fines that can be imposed for various types of social misconduct," says Eugene Tan, an associate professor of law at the Singapore Management University.

And despite the change in the law in 2004, "one would be hard-pressed to find people chewing gum in Singapore," Tan says.

He personally doesn't miss it.

"The footpaths look a lot nicer without the ugly gum marks," he says.

Image copyright AFP Image caption Gum on the pavement at Oxford Circus, London

A Singaporean student studying in London, Pei-yi Yu, also sees advantages in going gum-free.

"I have often had the unpleasant experience of getting my body parts into contact with both fresh and stale chewing gum in lecture theatres and classrooms," across the UK, he says.

In Singapore "we have a clean environment" he adds - thanks to Lee.

Plate, who has visited Singapore more than a dozen times, has never had any problem complying with the law, though he says his Berkeley-educated wife was tempted to walk on the grass.

Singapore is "excessively cleaned, overpriced and over-policed," he says - not that different from his own home town, Beverly Hills in California.

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