This is the first spiral-circle illusion among the ones you have posted which actually has circles and not just apparent circles. In the others, even the circles are illusions, as they are not actually there!
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Zöllner spirals: Concentric circles appear to be spirals (spiral illusion of the Zöllner illusion).pic.twitter.com/dtYar6TrBk
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I swear, one of these days you’re gonna sneak an actual gif in there and I wouldn’t notice the difference.

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Thanks. Twitter will use this to make your timeline better. UndoUndo
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