Is the cat going up or down the stairs?

I have copied the image into Photoshop and looked at it at a high magnification, and I can see fuzziness in a halo around the edges of cat's tail and back, which you can get when you weld two images together in Photoshop. does anyone else have Photoshop and can do the same thing? Or any other photo editing app which can go in close to the pixels?

I would say going down. The stairs appear to show an overhanging lip. If the cat was going up the stairs the step would have a raised lip at the end of the step which would present the steps with a dangerous trip hazard.

Neither up nor down. It's on the level.

How clever, boggles, I think you're right!

The staircase etc. is just a trompe l'oeil.

I agree

It doesn't really matter whether the cat is going up or down because as soon as it gets where it is going, it will turn around and go back where it came from.