Are there more doors or wheels? Football's brightest minds are on the case, with the stars of Premier League sides Manchester City and Tottenham, as well as MLS outfit Philadelphia Union searching for the right answer.
Much like the blue and black dress phenomenon and 'Yanny or Laurel', it is a question that has threatened to break the internet, with everyone wondering if there is a greater number of doors or wheels in the world.
So what do Jack Grealish, Harry Kane and other footballers think? GOAL brings you the details.
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Are there more doors or wheels in the world?
In the absence of an itemised list of doors and wheels, it is practically impossible to know the answer to the question, but Kane is in no doubt that there are more doors.
"Doors, without question, think of all the cupboards," reflected the England and Spurs captain. "I was going around my house yesterday, there were five times the amount of doors. It’s not even a debate for me.”
Kane's partner-in-crime Heung-Min Son took a different position though: "I’ll say wheels, just think of one car - it has four wheels."
The debate also gripped the Manchester City training session this week, as Grealish posed the question to his team-mates, but the conundrum left Rodri flummoxed and he decided not to give an answer.
Kyle Walker thought a more interesting question to ponder was: "Are there more grains of sand on earth than there are stars?" It's a good question.
The question has crossed the Atlantic too, with Philadelphia Union players getting in on the debate.
The majority of the Union stars seem to come down on the side of wheels, with lego cars and model car toys being cited as an example of the proponderance of the circular objects.
At Crystal Palace, Connor Gallagher, who is on loan at the club from Chelsea, reckoned that wheels won out, saying: "Definitely wheels. Does a cupboard count as a door? I'm saying wheels still!"
However, the Eagles are a divided camp, with Nathaniel Clyne declaring: "There’s more doors, everyone’s got a door, so I’ll say more doors than wheels."
Where did it come from?
Like any internet sensation, it can be tough to firmly establish the origin, but it took on some virality in March 2022 after Twitter user Ryan Nixon brought a playful debate between friends online to get some outside perspective.
He received a whopping 223,000 replies to his Twitter poll, where wheels edged the votes with a 53.6 per cent majority.
As it turns out, Ryan was not the only person who was 'here for it', and the debate has since been all over social media with the Spurs, Man City and Palace camps all investigating the question.