Do you see a red pill or a blue pill? Facebook’s mind-bending optical illusion

Facebook's chief scientist used this clever illusion to demonstrate how the human eye 'takes its best guess and sends that to the conscious mind' at the company's annual F8 conference. Look at this image, do you see a red pill and a blue pill? If so, your eyes are not giving you the full picture. In fact, both of these pills are grey. Speaking at the San Francisco event, Michael Abrash, who works for Facebook-owned virtual reality (VR) experts Oculus, used the illusion to show how virtual reality can be observed as reality. Abrash explained that both pills in the illustration were actually grey, yet when the human eye is presented with a red or blue background, the colour appears to change. "While science fiction novels gave me the conceptual framework for thinking about [virtual reality], it was The Matrix that made me believe in it." he said. "Even though it was based on technology that won’t exist for decades, if ever, The Matrix gave me a deep sense of what VR could someday be like." “Virtual reality, done right, really is reality, as far as the observer is concerned,” he concluded.