Do You Really Believe Everything You See?

Optical illusions are fun but they also have an indirect, yet deep philosophical point to make: Don't always trust what you see. Perhaps the most common - and unintentional - fact that humans ignore is that optical illusions occur in our everyday lives. The optical illusions that you see in print have two important aspects. First, you are told it is an optical illusion. Second, the optical illusion is optimized to demonstrate its illusion.

Source (http://upload.wikimedia.org/wikipedia/commons/8/89/Scintillating_grid.jpg)

The graphic above is an optical illusion; there are white dots at every intersection but you can only see the white dots that you're looking directly at. What if you weren't told that you were looking at an illusion? What about the photo below?

Source (http://www.moillusions.com/oldboy-optical-illusion.html/kid-dad-op-ill/)

Who is holding who? If I didn't tell you this was an optical illusion, what would you think of it? There has to be some trickery, right? Below is the same picture, but I've traced where the child's face is; he's being held by a man whose face is on the right side of the red line, serving as a well-blended backdrop for the child's face. The child's face also traces out as if it was a shadow on the man's face.

The point is that you have very valuable senses, such as sight; however, those sense aren't always telling the truth and there's nothing you can do about it. You will experience optical illusions like this all of the time and most of the time you won't even know about. The next time your "intuition" tells you something different than what another sense is telling you, consider listening to it.