Is this a circle or a spiral? It looks like a spiral, doesn?t it? However, if you trace the line from the outside in or from the middle to the outside, you will not reach the middle or the outside because this isn?t a spiral, this is a clever image made up of concentric circles.
It works because the black background of the ?spiral? draws your eyes in to the central focal point. The circles are not formed out of solid lines, but mixed shades of black and white to give them the illusion of leading inwards, like a spiral.
Looks like a spiral, right?
Wrong... It's a bunch of independent circles
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