What exists, let us call it X. Then X is whatever it is, but what any apparatus of cognition (for example, a human mind) will cognize it to be, will also depend on that apparatus of cognition. No apparatus of cognition sees what is actually existing as it really is but only from its own unique perspective and limitations. Because all apparatuses are more or less different from one another to different degrees (they can be similar but can never be the same), so X will be cognized differently by different cognizers; and no one will know what X is . That is the relation of all cognizers to what is actually existing or happening.
The crucial point here is to remember that whatever is actually existing is X and not a table, a chair, an atom or a molecule etc. because a chair or molecule etc. is what results after the cognitive activity of that particular cognizer from his own unique perspective which is different in varying degrees from the perspectives of all other cognizers in the universe.
The reason why human beings in everyday life seem to have similar views of tables, chairs and mountains etc. is that because their cognitive apparatuses are similar enough to each other to reach at a working consensus. This may not be so between different species or between proto humans, humans and post humans or between humans and some other unknown kinds of life in the universe.
Anything which anyone can know is relative to him and from his unique perspective. All knowing is perspectival and anything which humans know is known only from human perspective. The universe which human scientists know is human universe and not what actually exists or is actually happening.
So the huge mistake in common thinking is this: When someone perceives “a chair”, he (the knower, perceiver or cognizer etc.) jumps to the conclusion that what exists there is a chair and that the chair has an absolute existence of its own independently of him and that he is a mere spectator of the scene and has no part in making the scene.
Your thoughts?
Logic and Mysticism 
Thanks Atul for your comment.
“Reminds me of postmodernist theory”
Interesting observation!
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Hi,
You wrote to me:
Andre, You wrote, “when one “proto scientist” first understood that there was an “objective” reality outside of us which we could use and manipulate for our benefit.
What do you consider to be this “objective reality”? Kant’s thing in itself?
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I answer in Ask a Philosopher but the answer did not yet pass Jürgen Lawrenz’s moderarion.
You can see the answer here:
https://agaudreault.wordpress.com/for-me-objective-reality-in-askaphilosopher/?preview_id=4653&preview_nonce=2e5ec841bc&_thumbnail_id=-1&preview=true
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We perceive reality as a set of “qualia” produced by our brain in reactions to the stimuli we receive from the environment. These Qualia (Daniel Dennett) are Plato’s shadows, which our “minds” perceive as the reality “out there,” It is not but only “appearance” of it. Dennett argues that Qualia do not exist. They do. What does not exist is the reality that they present to our minds.
I am presently writing in absentia a Ph.D. dissertation, De evolutionibus res naturas, which will do to our “understanding” (Kant) of reality what Copernicus’ De revolutionibus rerum caelestium did for our perception of our place among the star.
I will publish it in Medium and agaudreault.wordpress.com.
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