As already touched in the introduction of this series, the only way we experience reality is through our senses, in particular through the interpretation the brain makes of the raw data received by our sensory system in a specific frame of reference.
The senses are the only medium we have between our consciousness and the external world, but their inputs to our brain must be processed in an analytic way or we risk to be fooled by our own senses!

How we perceive the senses?

Traditionally the senses are five: Sight (vision), hearing (audition), taste (gustation), smell (olfaction), and touch (somatosensation) , but there are at least five other major senses as shown in the image below.

Source

The capabilities of the receptors vary from species to species, but also from person to person.
It is very well proven that people who lost sight gained a better sense of hearing, one exceptional example is Daniel Kish who claim he can use sounds to echolocate its surroundings somewhat like a bat does in the darkness.
Even though the quality of raw data received from our eardrums may be different from the one Daniel Kish receive, we can confidently say, while listening to the Moonlight Sonata by Beethoven, we will hear the same notes.

Vision works almost in the same way, but much more differently than we may believe.
Think about what colors are and try to explain them to a blind person who has never seen a color in his life. You may start from Blue and Red saying that the first one is colder and the second one is hotter, but this would be a description based on your association of those colors to some climate phenomena you are used to, like a cold snowy day or a hot sunny day.

So it's not easy to give a universal explanation of nature based solely on the senses, we must take in account the way information is treated by the brain.
So once we have the raw data in our brain, how does it processes it?
The brain is not an error-free machine, in fact it is subject to something we call…

Illusions

The brain is “lazy” and tries to use as less energy as possible when performing an action.
Take into consideration your sense of Vision once again, your eyes make in focus just a single central portion of what you see, the rest you perceive as vision is just an attempt of the brain to make sense of the image we are receiving.
So your actual eyesight is not as good as you may think, even if you do not wear glasses, this phenomenon can be observed through this visual illusion.

Source

Try to see the black dots inside the intersections of the grey lines and you will find that while gazing your eyes around the image some black dots may disappear while not looking directly at them. This happens because what we really see is the zone we have in the center of our view while the surroundings is the result of what the brain thinks there is, an approximation of reality.

Illusions are not a prerogative of Vision, in fact there are Auditory illusions, Taste illusions (try to think eating a juicy lemon slice), and so on.

So if we cannot fully rely on our senses or the way the brain interprets the data from them, how can we even imagine to have an accurate and objective description of reality and say we can understand it?
For this answer we'll have to wait for the next post.

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Thank for Reading!

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Until next time!