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IT'S a simple, black and white drawing from 1892.
But it's also an optical illusion that captivates psychologists, philosophers and... Mikel Arteta.
The sketch-like image can be seen as a duck or a rabbit, sometimes just depending on which side you start looking from.
But for the Arsenal boss, who has signed a new three-year contract ahead of Sunday's trip to Spurs, the picture is all about being on the SAME side.
First things first, though. What's the drawing SUPPOSED to indicate?
Experts have focused on two areas.
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The initial point is that what you usually see can depend on your own situation - not just your distinct personality.
That means your environment, upbringing and even the time of the year can effect your thinking.
Swiss people, for example, tend to see a bunny rabbit at Easter and a duck in October.
However, the second use for the drawing is more exciting.
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It's reckoned it can help test how creative you are.
The faster you can change from seeing a rabbit to a duck - or vice versa - the more creative you are.
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But Arteta's own use for the image is very different.
He doesn't mind if it's a rabbit or a duck that his squad sees, as long as they ALL see the same thing.
The Spaniard explained why on show.
He asked documentary makers to tell him what they saw - and got contrasting replies.
Arteta then told them: "This is the most difficult thing in a football club...
"My only aim is that everyone sees the duck or the rabbit because if you see a duck and I see a rabbit we are on a different pathway, a different direction."
He added: "I think we are starting to get in line where we are all seeing the duck"
Arteta is convinced such unity can keep his players on the straight and narrow - mentally.
He said: "I think there's a thin line between confidence and complacency.
"Winning is something, deserving to win is another thing, and to perform to a level that we want is a completely different thing."
Some people claim that, whichever you see first in the picture, you can't unsee it.
But Arteta hopes the message from the picture is wholly different.
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It's this: Once you learn a single purpose, you can't unlearn it.