First a dress divided the internet, now a new debate is sweeping the web - and it's all over a humble tabby cat.

At first glance the moggy in a black and white photo looks as if it is walking down a flight of stairs, but look again and the image appears to flip.

Some insist the cat is travelling downstairs because of the step edges and the bright patch behind the pet.

But others say the image is looking down onto the top of the steps, each of which has a raised grip on it. They claim the light patch is the floor at the bottom.

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This image of a cat on a flight of stairs has divided the internet. Some see it walking up and others say down

A post of the image by 9gag.com has received more than 3,600 comments and has spawned several YouTube videos attempting to explain the illusion.

THE GOLD AND WHITE DRESS THAT WAS ACTUALLY BLUE AND BLACK It was a question that divided the internet: was a dress white and gold, or blue and black? The two-toned frock sparked a fierce online debate, with social media users arguing about the colours they saw. Psychologists explained that the reason for the division was the picture had created an optical illusion. Objects reflect light at certain wavelengths, or colours, and the human brain determines the colour of an object by taking in its reflected light. But this perception can be thrown off balance by the colour of nearby objects. With the photo of the dress, the surrounding colours are so muddled that the brain isn't sure what to make of the dress itself. Advertisement

Posting on YouTube, Jorge Rodriguez says the cat appears to be going up the stairs.

He said: 'At the bottom of the staircase appears to be a floor.

'That "concrete-like build up" on the sides of the ledge is perpendicular to the top of the stairs.'

Another YouTube user gave a more scientific answer.

Asango K said: 'The stairs could as well have stone blocks giving the cement its form.

'There are definitely small stones in the cement of these stairs, meaning that the material on the side we face was a fluid when the stairs were built.

'Those stairs could not be made like this if the picture was taken from downstairs.'

Posting on Facebook, Indra Rahmadhani said: 'Down. Why not Up? Look at the stairway.

This shows how colour balance in the camera that took picture of the dress created the optical illusion

Poll Which direction do YOU think the cat is walking? Upstairs Downstairs Which direction do YOU think the cat is walking? Upstairs 3308 votes

Downstairs 5089 votes Now share your opinion





'What kind of architect who design the stairs which can make pple (sic) stumble. It must be downside.

'Trust me, I'm an engineer.'

A later post on 9gag also showed an architect's approach that suggested the problem had been solved and viewers were looking at the front edge of the steps.

Others attempted to use biology.

Writing on Facebook Alfredo Rochefort Ciscutti said: 'It's going down. When cats go down the stairs, they raise their tail to mantain balance.

'When they go up, the tails remain down cause balance isn't an issue.'

The picture comes after a debate over the colour of a two-tone dress that was pictured on Tumblr.

While some people saw the dress was blue and black, others saw it as white and gold.

The dress caused such a sensation that it was tweeted by stars like Kim Kardashian and her husband Kanye West.

The makers of the dress, Roman Originals, later revealed that the dress was in fact blue and black.

This image of an impossible stair is an optical illusion that makes the steps look like they go both up and down