http://www.bbc.co.uk/news/blogs-trending-32251712
Ok it may be me, but the idea that this image is in any way ambiguous reflects the power of suggestion rather than any visual property of the picture. It is pretty obvious to me which way it is going.

Down

Is this cat going up or down the stairs?

Yes.

Ignore the whole image and look at the cat.

Its ambiguous for a moment but thats definitely a view of a staircase from the bottom, which sort of resolves any other ambiguity

Ignore the whole image and look at the cat.

If you do that it looks like a cat that might be walking

Camera looking up the stairs, if not, somebody built those stairs wrong!!

Up

will this cat get rescued or come down itself.

Ask the cat?

Up.

If the cat’s going up the stairs then they’re **** lethal stairs.

Camera looking up the stairs, if not, somebody built those stairs wrong!!

+1

Just look at the side plates.

Down – tread noses and shadows are a dead giveaway.

Down as per the side plates.

Purrty cat is going down … 😀

Neither, if you look very carefully you will see that in the photograph the cat is absolutely stationary. A trick question to catch out the stupid who think it is going up and the even more stupid people who think they are clever because they have made a study of the construction of stairs. And anyway who’s to say no ones taught the cat to walk backwards. 🙂

It’s doing both. It’s the little-known corollary to Heisenberg’s Uncertainty Principle.

Neither. It is going to shit all over my garden.

The nosings on the stairs give you the answer

Can cats look up? I know dogs can’t.

Also what if the cat is actually walking backwards?

It’s on it’s way back down to Schroedinger’s box

What if it’s actually an escalator?

It’s not actually a cat, it’s just a figment of your imagination…… (the stairs however are completely real)

😉