This is probably the best illusion I've ever seen. The blue and red lines are all the same length; none is moving or changing size, and they’re all at the same level. Only the arrowheads are moving. https://t.co/bDyeOKXgbC pic.twitter.com/V6KrmLkiPr
— Steve Stewart-Williams (@SteveStuWill) October 4, 2018
(Tip of the cap to Marcel Salathe.)
