Reality is an Illusion

Actually this should read:
Reality is not perceivable as such, and what we perceive as Reality is a filtered version so we can take action and live in the World.

There are too many details to be perceived and most of them are of no use to the present situation and are therefore not processed by the brain.

Cannot see it all
The first limitation is spacial and temporal, one cannot be everywhere all the time.
Obvious one might say, but that statement has a corollary truth in it, that is we cannot know what led something or someone to be as is when we encounter it.
So we just see the end result and appearances can be misleading.

We also cannot perceive what is out of sight or earshot. So the hidden part of things is not available for analysis. The back of cards, the inside of a box, etc.

Of course, we can be easily aware of this limitation but it is difficult to keep in mind what is unknown. We will quickly forget that we don’t know what we don’t know and make a certainty of the part we can perceive.

We are missing what is missing.
— David McRaney, You Are Not So Smart.

Sensory Limitations

Then there are limitations from our toolbox.

  • Our eyes can only see some wave lengths and have a limited resolution.
  • Our ears can only capture a certain range of sounds.
  • Our skin can be sensitive to pressure only to some extent.
  • Our nose can only sense a limited range of smells.
  • Our tongue can only distinguish five tastes.

It is a fact that

  • Cats can hear sounds inaudible to dogs,
  • Dogs can hear sounds inaudible to teenagers,
  • Teenagers can hear sounds inaudible to adults.

Bees can see infrared and pigeons can perceived more colors than we do. Cats vision has major differences to the one of humans. So what we call Reality is different for everyone. Even between humans. Near sighted people’s world is different than other people’s world.


In fact, our fives senses of sight, smell, hearing, touch and taste, are not designed to capture all the emissions from the outside world, but to capture what is essential to our survival. For instance we are unable to sense the direction of the Earth magnetic field because it would be useless information to us but migratory birds can sense it because it is an essential information to them. Yet this magnetism is constantly present as a compass can show.

Our sensory system main function is actually to discard what is useless more than capturing what is useful. Otherwise there would be way too much information out there to deal with. (Gamma rays, Microwaves, Xrays, Radio waves, etc.)

The information is there but we are oblivious to it although we are bombarded with it all the time. The proof is, a cell phone in our pocket will capture some radio waves we are unaware of.

Then the limitations of our own brain. Not everything that is received by the ears, eyes and skin is ever translated into neural stimuli and not even a millionth of that is ever reaching the conscious brain and what does has been tweaked by many other things.

Our Paradigm

These filters are influencing each other and precedence is hard to define, yet the mother of all brain filters is our Paradigm.

Our Paradigm is the set of psychological filters we have in place. It is our view and opinion on the world. It is made of our preferences, our prejudices, our fears, our hopes and desires. Most of them are actually totally hidden in our unconscious. Their actual motivation and origin are often unknown. We don’t even know we base our opinions and judgment on that set of filters. They are often created in infancy and are usually difficult to identify and even harder to change.

The Paradigm is what stops most external stimuli from reaching the conscious brain. Although that filtering is a necessity because our conscious brain (NeoCortex a.k.a. Brain 3.0) cannot handle the millionth of what the sensory brains can capture, it of course leads to a major distortion of the original facts.


Another set of filters is all the influences from external sources. Psychologists call these Primers, Anchors and other fallacy generators. Advertisement and marketing are very fond of these entry points. But anything in sight can do the trick (after having been filtered by all the above, of course). For instance, Daniel Kahneman (Thinking Fast and Slow) demonstrated that a randomly picked number can influence how many African countries people estimate to be members of the U.N.



There are the Fallacies and Delusions. These are natural behaviors based on primal experiences and driven by basic instincts. We all have them, they are part of the human toolkit and are due to various interactions between the three main parts of the brain (1,2 and 3). They are the Confirmation Bias, the Self-Fulfilling Prophecies, the Loss Aversion, the Hindsight Bias, etc.

I highly recommend you seek to get more information about these fallacies on David McRaney’s Blog, You Are Not So Smart. He is the master of Delusion.

These Delusions are shaping how we perceive the world.
For instance 25% chance of dying from a treatment seems a lot more dreadful than 75% chance of surviving. The odds are the same but the perception is different. That is Loss Aversion to you.
We cannot help it.

Present various medical papers discussing the same treatment with the same 25/75 distribution to a group.

  • Pessimistic people (and opponents of the treatment) will remember the treatment
    killing 25% of patients.
  • Optimistic people (and supporters of the treatment) will recall the treatment
    saving 75% of patients.

That is Confirmation Bias.
We see and seek what we want to see and find. We will read in depth what supports our Beliefs but only give a superficial look to what does not. Unless we are looking for its flaws, of course…

Awareness is the best weapon against Delusions. When asked about the chances of her husband John Kerry to be elected president, Teresa Heinz, aware of the Confirmation Bias, replied: “I don’t know, we only mingle with Democrats”.

Fill in the Blanks

So when we have all the fact we will already distort them.
But in real life we usually don’t even have all the facts.

So the brain is filling the blanks.
When something is amiss, the brain cannot accept being unable to figure it out. It must come up with an explanation so to be able to act on it. The brain resolves ambiguity using prior knowledge and other factors such as personal preferences and all of what constitute our Paradigm.

The feature image of this post is just a hash of lines but everyone can see a Heart in it.

This capacity was intended to resolve life threatening problems with limited information and is what makes doing crosswords or optical illusions entertaining but has its drawback when unaware and unwilling to admit its influence because we can come to being certain about things that are partially fabrications.


Another filter is context.

  • In a room filled with people we hear many voices but ignore most of them.
  • At home, we are attuned to each familiar voice and can immediately react to them.
  • In the wilderness, the slightest hint of human voice would prompt immediate attention.

Our perception of Reality is actually more like the game of the Chinese whispers, in which one person whispers a message to another and the message is passed through a line of people. Usually the end product is a distortion of the actual original message for the great amusement of all.

Here the participants of the game are replaced by our senses, preferences, opinions, external influences, delusions, fallacies, filling-the-blanks fabrications and context.

Do not be so sure of what you call Reality. Take the time to question your own perception. Be aware of your own filtered perception.

Take a second look before crossing the street, that car might not be double parked after all.