Imagine for a moment that the world that you see around you is partially an illusion, a figment of your imagination constructed by your mind. Imagine that everything you think you know based on what you see is in fact a lie...
We are all partially blind. There is a part of our eye that lack the ability to interpret the spectrum of light that it should then transfer to our brain to form images. This part of your eye is called scotoma, or the blind spot. Despite this physical fact you do not experience that a part of your vision is missing or even blurred. This is because your brain is compensation for this missing information by filling out the blanks with what it anticipates should be there.
We all spend our lives with a small portion of our visual experience made up, like a virtual reality that is created deep within our brain. When you consider this fact and the fact that you probably never ever considered that a small portion of the things you see may not really be there, or is slightly off because our brain guessed what should be there incorrectly for a split second...then perhaps you will open your mind to the possibility that what you see is not as certain that you think and that your brain have the ability to see far more than you think.
The way we see the world around us is for many the most important way we have to verify what we perceive as our reality, but have you ever experienced that despite being right where something happen you did not see it happen? This is called change blindness and it means that
It is not your eyes that dictate what we see, they are just the organs that send interpreted information about wavelengths of light. It is in your brain that this information is constructed into images and it does not always do so in the way we would like it to depending on many different factors. In fact it is safe to say that even if a hundred people watched the same sunset it would still be one hundred different interpretations depending on the subjects mood, age, state of mind and a hundred other factors.
There are also a lot of information given through your vision that you remain unaware of. Information that is handled and processed in your subconscious that still have a lot of impact on how you respond to what you see. Body language, patterns, measurements like the golden ratio and what happens in our peripheral view. All of these bits of information is processed in your brain subconsciously and yet you make hundreds of decisions based on the result.
So in many ways what you believe you see may not be true at all, but rather a construct created by your mind based on information you are unable to access or control. Information that the brain can not process may simply be disregarded. Furthermore what you see may cause you to act on emotional impulses based on subconscious triggers, which in turn can make things that you look upon seem different than they actually are.
Imagine for a moment that all of this occur to you at every moment of your life and then consider the fact that you have an additional four senses that are susceptible to how your brain interpret the information you get from them. Now I ask you...what is reality and what is a construct of your brain?