Seeing is not believing, and your entire life has been a lie. Just keep your eyes on the cross and you'll know soon.
Source: This fantastic reddit thread.
Mind = Blown. Right?
The Science behind this trick is amazing. Basically everything you see from the corner of your eyes is distorted, yet you've never really paid any attention to it. It may also be the reason why you are always looking at your nose - literally, at all times - but the brain ignores the visual until you focus your attention to it.
This effect was recently discovered - completely by accident - by Sean Murphy, an under graduate student. It was part of a research project led by Cognitive Scientist Matthew B. Thompson .
In case you are having trouble loading the rather large .gif file, you can just watch the video below for the same effect.