Are there more doors or wheels in Philly? An investigation.

In an offbeat and sometimes furious viral argument, people on social media are judging whether there are more doors or wheels in the world. But what about in Philly?

TikTok has registered more than 71 million related views since the debate began roiling on Twitter on March 5, when a man in New Zealand announced, “My mates and I are having the STUPIDEST debate. ...” In an unscientific vote based on the tweet, 223,347 people responded: 46.4% went for doors, while 53.6 saluted wheels.

Late-night TV hosts, CNN, the Today show, YouTube, and newspapers around the globe have featured the fervid back-and-forth between Team Doors and Team Wheels.

Of all the topics that bubble, simmer, and seethe on social media, it’s hard to imagine that a prosaic inventory of everyday items could command so much attention.

Can anyone explain it?

“When a meme like this captures the imagination, we try to nail it down,” said psychologist and professor emeritus Frank Farley of Temple University. “But there is randomness and unpredictability in human behavior we can’t explain.

“Maybe we’re simply using the debate to get away from the relentless barrage of horrors in the world.”

For some, doors vs. wheels is reminiscent of the digital hullabaloo of 2015, when online society couldn’t decide whether a dress was blue or gold. Three years later, people went a little bit nuts over whether they were hearing the names “Laurel” or “Yanny” in an audio clip.

What many people like about the doors-wheels conundrum is that it seems like an argument you could have without offending anyone — no small feat during fraught times.

Karl Paranya, a high school math teacher at Friends’ Central School, a Quaker institution in Wynnewood, said: “It’s an impossible question to answer. But we could try to solve it anyway.”

Using his estimated 400-by-400-meter campus as a template, he said he’d divide it into 10-by-10-meter boxes, then randomly pick around 100 boxes to which he’d send his 100 students, where they’d catalog any wheels or doors they found and average them together. He would use that number as a representative sample, with margins of error, to extrapolate an approximate answer.

“I even find flaws in what I’m thinking,” Paranya said humbly. “It may not work.”

Some other folks in the Philadelphia region offered more definitive answers.

Andrew Busch, a spokesperson for SEPTA, got right down to details: Each train car has eight wheels. There are six side doorways. But each doorway has two sliding doors. Cars also include a door on either end, and a door to get into the operator’s compartment.

That makes 15 doors in one car. Because there are 600 SEPTA train cars, we wind up with around 9,000 doors and 4,800 wheels.

As for buses, there are 1,400 of those, each with six wheels and two doors, making for 2,800 doors and 8,400 wheels. And each of 60 trolleys has two doors and eight wheels, totaling 120 doors and 480 wheels.

So, in the SEPTA universe, wheels trump doors, 13,680 to 11,920.

If only the rest of life were that simple.

In Philadelphia, a determined problem solver might get part-way down the road toward discovering whether this is a doors or wheels town. But they’ll eventually get lost in the thicket.

For example, Census figures show there are around 690,000 housing units (private homes and apartments) in Philly, 300 high-rises up to 330 feet, and 56 skyscrapers 330 feet and taller. This says nothing of stadiums, arenas, warehouses, and other places.

So, how many doors is that?

Conversely, the city population drives roughly 750,000 vehicles of various fuel types, according to PennDot, which could mean there are 3 million tires (four times 750,000).

Is that the total wheel count? What about motorcycles and bikes? Even the Bicycle Coalition of Greater Philadelphia can’t say how many bikes the city boasts, though it knows that 14,000 workers commute by bicycle at least three times per week.

Christina Bicchieri, a philosopher and psychologist from the University of Pennsylvania, votes for doors. “I have many more doors than wheels in my life,” she said. “I think that’s true of a dense urban area with so many buildings like Philadelphia.”

Realtor Christopher Plant, who often works in Germantown and Mount Airy, declares himself a door man, possibly because, he admits, he sees so many in his inventory. “Apartments have eight to 12 doors, not including cabinets,” he said. “There are so many enclosures in everyday life.”

But thinking about doors as just the wood that hangs between rooms in a home is too limiting.

As Julie Drzymalski, director of the Industrial and Systems Engineering program in the Temple College of Engineering, said, “You have to identify what exactly is a door and a wheel.”

And that gets sticky.

For example, you have: Ferris wheels; wheels beneath computer mouses, gear wheels whirring in endless circles in millions of machines, chair wheels, car wheels, and, for that matter, wheels for any mode of conveyance except tanks and snowmobiles. That’s just for starters.

As for doors, there are: front doors, basement doors, office doors, cabinet doors, car doors, glove-compartment doors, lockers, and elevator doors — to name a few.

“There are even doors under the hoods of German cars,” noted Dave Johnston, a mechanic at Lehmann’s Garage in Chestnut Hill. Those are hinged doors to access brake fluid. “Some cars even have fuse-box doors not everyone notices,” Johnston added.

Other questions come up: Revolving doors possess both wheels and doors, so how do you count them?

Complicating things further, Jeff Davis, a product designer in Chestnut Hill, said: “What I see in everyday Philadelphia are lots of wheels, since wheels are anything that spin on an axle.

“That means doorknobs are actually wheels. The hinges on doors can be called wheels. So, there’s a wheel on every door, but not a door on every wheel. That makes me Team Wheel.”

He has a teammate at the Liberty Science Center in Jersey City, where president and CEO Paul Hoffman trash-talks door folk:

“Team Wheels blows Team Door’s doors off,” he scoffed.

Hoffman finds wheels everywhere: “There are 1.4 billion cars on the road, [worldwide] plenty of them two-doors. One billion bicycles exist in the world. Every year Mattel manufactures 2,081,376,000 wheels for Hot Wheels. Lego makes 380 million wheels for its toy kits. The skateboard industry produces 6 million wheels annually. This makes doors dead as door nails.”

Regionally speaking, the answer might depend on where you live, says Girija Kaimal, professor in the creative arts therapies at Drexel University. “Philadelphia has more doors, its suburbs have more wheels — I think.”

Regardless, she added, “this is a fascinating intellectual exercise. But let’s face it, nobody could ever prove their point, so there can be no right or wrong answer.

“And that’s the fun of all this.”