Why do we behave so oddly in lifts?
Many of us use them several times a day without really noticing. And yet the way we behave in lifts, or elevators as they are known in the US, reveals a hidden anxiety.
"Most of us sort of shut down.
"We walk in. We press the button. We stand perfectly still."
Taking the lift could be the least memorable part of your journey to work, but Dr Lee Gray of the University of North Carolina at Charlotte has made it his business to scrutinise this overlooked form of public transportation. People refer to him as "the Elevator Guy".
"The lift becomes this interesting social space where etiquette is sort of odd," he explains. "They are socially very interesting but often very awkward places."
Passengers seem to know instinctively how to arrange themselves in an elevator... like the dots on a die. With each additional passenger, the bodies shift, slotting into the open spaces.
The goal, of course, is to maintain (but not too conspicuously) maximum distance and to counteract unwanted intimacies - a code familiar (to half the population) from the urinal bank and (to them and all the rest) from the subway.
The New Yorker: Up and then down
Conversations that have been struck up in the lobby tend to be extinguished quite quickly in the thick atmosphere of the office elevator. We walk in and usually turn around to face the door.
If someone else comes in, we may have to move. And here, it has been observed that lift-travellers unthinkingly go through a set pattern of movements, as predetermined as a square dance.
On your own, you can do whatever you want - it's your own little box.
If there are two of you, you take different corners. Standing diagonally across from each other creates the greatest distance.
When a third person enters, you will unconsciously form a triangle (breaking the analogy that some have made with dots on a dice). And when there is a fourth person it's a square, with someone in every corner. A fifth person is probably going to have to stand in the middle.
Now we are in uncharted territory. New entrants to the lift will need to size up the situation when the doors slide open and then act decisively. Once in, for most people the protocol is simple - look down, or examine your phone.
'Get me out!'
Nick White was trapped in a lift in his office building for 41 hours.
I got into the elevator and pressed 43. There was a momentary dimming of the lights and a little bouncing of the elevator.
I waited for a bit, then hit the alarm button. There was just dead silence. At first I just kept pushing different sequences of buttons.
I was yelling up and down the shaft. I slapped the walls. I did get mad, I did curse, I did shout at the camera.
At some point, I opened the door about two inches and looked down the shaft at an infinite blackness. When I had to urinate I relieved myself down the shaft, with the idea that perhaps that could be a signal to someone.
At one point I was wondering if this was going to become my tomb - if they were going to open the doors and there's my corpse.
Eventually a voice came over the intercom and said "Is there someone in there?" I jumped up and I said "Yes, there's effing someone in here. Get me out!"
Why are we so awkward in lifts?
"You don't have enough space," says Professor Babette Renneberg, a clinical psychologist at the Free University of Berlin.
"Usually when we meet other people we have about an arm's length of distance between us. And that's not possible in most elevators, so it's a very unusual setting. It's unnatural."
In such a small, enclosed space it becomes vital, she says, to act in a way that cannot be construed as threatening, odd or in any way ambiguous. The easiest way to do this is to avoid eye-contact.
But perhaps there is more to it than just social awkwardness.
"In the back of our minds we are a little anxious," says Nick White, an office worker in New York who was unfortunate enough to be trapped in a lift for 41 hours.
"We don't like to be locked into a place. We want to get out of the elevator as soon as possible, because, you know, it's a creepy place to be."
During his ordeal, he began to think of another enclosed space that lurks at the back of our minds - a tomb.
It would be understandable if White refused ever to step in a lift again. But if you work in a city built on a vertical plane, and if you have aspirations above being a receptionist, that isn't an option.
"I certainly remember what happened to me every time I go in one," he admits. "It's part of the commute, the part you have the least control over."
Elevator Guy Lee Gray agrees that a sense of disempowerment is the main cause of lift anxiety.
"You're in a machine that's moving, over which you have no control. You cannot see the elevator engine, you don't know how it's working," he says.
Riding high - a history of lifts
• 1st Century BC: The Romans operate lifts using pulleys with human, animal and water power
• 1800: Steam-driven lifts are in use in English factories. An expert operator controls each car by manipulating a rope that passes through it
• 1853: Elisha Graves Otis unveils a safety device to prevent freefall, paving the way for passenger lifts
• Late 1800s: Stately "movable rooms" begin to appear in hotels and department stores - they feature cushioned benches and chandeliers
• 1950s: Safety systems that automatically close both sets of doors eliminate the need for operators
• Future lifts may employ magnetic levitation technology - a design has also been trialled for a lift to move vertically and then horizontally to navigate larger skyscrapers
This sense of passivity in the hands of a machine may become more pronounced as we enter the age of buttonless "smart" elevators.
After swiping through security or touching a central control panel, travellers are directed to a lift that has been programmed to stop at their floor, removing the need for any further commands. The system is designed to cut down on unnecessary stops, but although more efficient, some people find the experience unnerving.
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Regardless of the qualms and anxieties associated with lifts, Gray is adamant that they are safer than cars - and significantly safer than escalators.
"It is in in fact of one of the safest forms of transportation, if you look at the billions of miles that lifts travel every year and the very, very small number of accidents."
We all know this, which is why we continue to take lifts every day, despite our anxieties.
"We have learned that we can take an elevator and it is safe to do so," says Renneberg. "So in a way it's a triumph of rationalism over our more animalistic instincts."
This pleasing thought - that we become more sophisticated by travelling in lifts - is perhaps one to ponder next time you get in one.
Just don't, whatever you do, start a conversation about it.