If you've ever seen a viral optical illusion, you know that your eyes can't always be trusted. This visual trick from David Novick is a great example of that: From a distance the circles in the picture appear to represent four different hues, but look closely and you'll see they are all the same color.
The image above, created by Novick, a professor of engineering education and leadership at the University of Texas at El Paso, has been circulating around the web ever since it was recently shared on Reddit, Today reports. His "Confetti" picture is an example of the Munker illusion, which demonstrates the imperfect ways our eyes perceive color.
When you place a solid-colored shape behind bars of different colors, those bars influence how we see what's between them. Our brains want to fill in the gaps between the stripes. Depending on the surrounding shades, a circle that's really peach may look like it's "tinted" pink, green, or yellow.
This effect works best when the image is small or far away. Zoom in on the circles in the image above and their true color will become clear.
Color is a lot more subjective than you might think. According to a recent study out of Harvard, people are pretty bad at telling colors like blue and purple apart, and will even change their minds about their own perceptions when they're shown the same color a second time.