Look at the image and try to work out if the two figures are walking up or down the steps.
If you look at the figure furthest away, he appears to be walking down the steps, with the steps clearly defined against the green background. However, in the foreground, the figure appears to be walking up the steps. The lines and shapes in the foreground appear to be steps descending. We cannot agree whether they go up or down.
This is an illusion that tricks our minds because of line details showing how we expect steps to look and behave.
Are they walking up the stairs, or down?
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