No one has proposed an absolute monism that is universally accepted in any field. Philosophy and psychology stand out in this respect.
Why? Are people just perverse in refusing to acknowledge the truth? Possibly – but not likely.
Are people just too dumb to grasp the absolute truth about absolute reality? Possibly – but it is not necessary to assume this.
We are smart enough to grasp that there neither is nor can be an absolute reality, a non-zeroed eternal substance; we are thus more than smart enough to figure out what the absolute reality is if it were in fact existing. We are still smarter than that – we are smart enough to give the word “nothing” an empirical definition, so that we can write meaningful statements about nothing in a primitive, unempirical language of being.
We are also smart enough to realize that existence is not a perfection, but a limitation. To exist means to be limited, to be delimited to certain values of all characteristics, including degree of intelligence. The perfect is that which can exist only in concept, if even there. Sorry, Anselm, you too had it backwards.
Man is the epitome of an animal who sees things backwards.
I think we are pretty damn smart and crafty in our cleverness. Intellectually honest? Not at all. That is our biggest failing.
Man is the apotheosis of an intellectually dishonest animal.
Man is a rational animal in whom reason “fusts unused.”
Man is an animal who uses reason malignantly. A lame rewording for the lame of mind: man is an animal who ill-uses reason.
Man is an animal with an inverted “soul” – psyche, mind.
Plato’s simple characterization of the human psyche as being made of 3 parts: reason (Aristotle’s definition of man as an animal possessing reason inheres in Plato’s view of the soul), emotion/spirited element (valued so highly because this element is capable of displaying courage), and appetites (like the Freudian “id”). An inverted soul is any soul not ruled by reason. (Not to over-criticize Goethe, but I do not believe his soul was dominated by reason; he fell far short of Socrates and Plato in this critical aspect of rationality, and Nietzsche’s apotheosis of Goethe and his criticism of Socrates as being overly logical, and his cheap shot in referring to Socrates as “rachitic” in part reflect a deficiency of rational thought and rational “control” of the impulses and emotions in both Nietzsche and Goethe).
All of these “essential” definitions of man have a different emphasis, but are in fact equivalent in all important respects – they are all likely derivable from the true essential definition of man, which is yet to be discovered.