perception is everything

The theme of this video is that what we see isn't always real. Our brains get manipulated based on what we are trained to see and what we have seen in the past. For instance, there could be two different people in the same room. They have had different lives and are obviously different people. The room could look entirely different to those people even though it is exactly the same. This is because these people have had different life experiences, they were brought up differently and even thier eyes just see things differently. looking around the room thier eyes pick up different objects and leave others out, even the colours they see are different and things are seen in different context. I have experienced this when looking at some optical illusions. The ones where if you look at a seemingly random pattern a certain way and you are supposed to see the 3D image in front of it. Some people are able to do this and some people arn't. I personally have never seen the image! Optical illusions and tricks of the light surround us continually, our brains just interpret them the way it has made sense to in the past. The question this video is asking is how do we know if what we are seeing is real or not?