Your Lying Eyes

Who's up for a good optical illusion? The Blaze put us on to this one:

The two parts of the object in the image are actually the same color and brightness. You can demonstrate this by placing your finger over the seam that joins them.

The whole weirdness of it is explained here, but good luck trying to understand it.

Maybe part of the explanation is that our eyes assess the object's background as they view the object. An object viewed against a bright background appears darker than does the same object viewed against a darker background.