The Marginalian
The Marginalian

How We Know What We Know: The Art of Adaequatio and Seeing with the Eye of the Heart

A timeless guide to “understanding the truth that does not merely inform the mind but liberates the soul.”

“What is essential is invisible to the eye,” Antoine de Saint-Exupéry memorably wrote in The Little Prince. Indeed, in our quest to perfect thinking, could we be neglecting those deeper, more intuitive gateways to accessing the essential? Susan Sontag memorably argued that the false polarity of intuition vs. intellect imprisons us, but the question remains — how do we really know what we know? By what mechanism can we truly make sense of the world and our place in it?

A decade after his influential clarion call for prioritizing people over goods and creativity over consumption, British economic theorist and philosopher E.F. Schumacher turned to this delicate subject in his 1977 essay collection A Guide for the Perplexed (public library) — not to be confused with this Werner Herzog gem of the same title — in which Schumacher also explored how to map the meaning of life.

Schumacher considers the concept of adaequatio:

What enables man to know anything at all about the world around him? … Nothing can be known without there being an appropriate “instrument” in the makeup of the knower. This is the Great Truth of “adaequatio” (adequateness), which defines knowledge as adaequatio rei et intellectus — the understanding of the knower must be adequate to the thing to be known.

Building upon his notion of the five Levels of Being, Schumacher bridges the physical and the metaphysical:

Our five bodily senses make us adequate to the lowest Level of Being — inanimate matter. But they can supply nothing more than masses of sense data, to “make sense” of which we require abilities or capacities of a different order. We may call them “intellectual senses.” Without them we should be unable to recognize form, pattern, regularity, harmony, rhythm, and meaning, not to mention life, consciousness, and self-awareness. While the bodily senses may be described as relatively passive, mere receivers of whatever happens to come along and to a large extent controlled by the mind, the intellectual senses are mind-in-action, and their keenness and reach are qualities of the mind itself.

Illustration by Vladimir Radunsky from On a Beam of Light: A Story of Albert Einstein by Jennifer Berne

He illustrates the spectrum of human ability as it relates to our capacity for adaequatio:

As regards the bodily senses, all healthy people possess a very similar endowment, but no one could possibly overlook the fact that there are significant differences in the power and reach of people’s minds… Beethoven’s musical abilities, even in deafness, were incomparably greater than mine, and the difference did not lie in the sense of hearing; it lay in the mind. Some people are incapable of grasping and appreciating a given piece of music, not because they are deaf but because of a lack of adaequatio in the mind. The music is grasped by intellectual powers which some people possess to such a degree that they can grasp, and retain in their memory, an entire symphony on one hearing or one reading of the score; while others are so weakly endowed that they cannot get it at all, no matter how often and how attentively they listen to it. For the former, the symphony is as real as it was for the composer; for the latter, there is no symphony: there is nothing but a succession of more or less agreeable but altogether meaningless noises. The former’s mind is adequate to the symphony; the latter’s mind is inadequate, and thus incapable of recognizing the existence of the symphony.

This spectrum plays out over and over in every domain of the human experience and, Schumacher argues, making sense of the world in an intelligent way requires that we understand where we fall on the spectrum of adaequatio in every domain of knowledge. Ignorant attitudes, he implies, result from assuming that something is not true or not valuable simply because we lack the adaequatio to grasp it:

For every one of us only those facts and phenomena “exist” for which we posses adaequatio, and as we are not entitled to assume that we are necessarily adequate to everything, at all times, and in whatever condition we may find ourselves, so we are not entitled to insist that something inaccessible to us has no existence at all and is nothing but a phantom of other people’s imaginations.

This pulls into question the notion of capital-T Truth as commonly used and pursued:

People say: “Let the facts speak for themselves”; they forget that the speech of facts is real only if it is heard and understood. It is thought to be an easy matter to distinguish between fact and theory, between perception and interpretation. In truth, it is extremely difficult.

In a sentiment that Philip K. Dick would echo mere months later in asserting that “reality is that which, when you stop believing in it, doesn’t go away,” Schumacher adds:

When the level of the knower is not adequate to the level (or grade of significance) of the object of knowledge, the result is not factual error but something much more serious: an inadequate and impoverished view of reality.

Illustration by Ralph Steadman for a rare edition of Alice in Wonderland.

But the most important determinants of our access to knowledge, Schumacher argues, are our direction of interest and our existing beliefs — something even truer today, not to mention more dangerous, in our age of filter bubbles, when we have an ever-harder time changing our minds. Schumacher writes:

The level of significance to which an observer or investigator tries to attune himself is chosen, not by his intelligence, but by his faith. The facts themselves which he observes do not carry labels indicating the appropriate level at which they ought to be considered. Nor does the choice of an inadequate level lead the intelligence into factual error or logical contradiction. All levels of significance up to the adequate level — i.e., up to the level of meaning … — are equally factual, equally logical, equally objective, but not equally real.

It is by an act of faith that I choose the level of my investigation; hence the saying “Credo ut intelligam” — I have faith as to be able to understand. If I lack faith, and consequently choose an inadequate level of significance for my investigation, no degree of “objectivity” will save me from missing the point of the whole operation, and I rob myself of the very possibility of understanding.

Our existing beliefs and baseline assumptions, on which our entire capacity for understanding is predicated, is very much a product of our era, cultural context, and what William Gibson so memorably termed our “personal microculture.” Schumacher writes:

The observer depends not only on the adequateness of his own higher qualities, perhaps “developed” through learning or training; he depends also on the adequateness of his “faith” or, to put it more conventionally, of his fundamental presuppositions and basic assumptions. In this respect he tends to be very much a child of his time and of the civilization in which he has spent his formative years; for the human mind, generally speaking, does not just think: it thinks with ideas, most of which it simply adopts and takes over from its surrounding society.

And yet, Schumacher urges, our greatest responsibility in cultivating true understanding is to question precisely those assumptions, directing at them the types of critical-thinking tools Carl Sagan advocated in his timelessly necessary Baloney Detection Kit and Lewis Carroll outlined in his four rules for digesting information. Schumacher notes:

There is nothing more difficult than to become critically aware of the presuppositions of one’s thought. Everything can be seen directly except the eye through which we see. Every thought can be scrutinized directly except the thought by which we scrutinize. A special effort, an effort of self-awareness, is needed: that almost impossible feat of thought recoiling upon itself — almost impossible but not quite. In fact, that is the power that makes man human and also capable of transcending his humanity.

One of Antoine de Saint-Exupéry’s original watercolors for The Little Prince.

Echoing the Little Prince’s memorable assertion that “what is essential is invisible to the eye,” Schumacher writes:

Only through the “heart” can contact be made with the higher grades of significance and Levels of Being.

Cautioning against scientific reductionism, he adds:

For anyone wedded to the materialistic Scientism of the modern age … higher levels of Reality simply do not exist, because his faith excludes the possibility of their existence. He is like a man who, although in possession of a radio receiver, refuses to use it because he has made up his mind that nothing can be obtained from it but atmospheric noises.

Turning to the timeless question of how science and spirituality relate to one another — a question previously addressed by such monumental minds as Carl Sagan, Isaac Asimov, Ada Lovelace, Alan Lightman, Buckminster Fuller, and Jane Goodall — Schumacher writes:

Faith is not in conflict with reason, nor is it a substitute for reason. Faith chooses the grade of significance or Level of Being at which the search for knowledge and understanding is to aim. There is reasonable faith and there is unreasonable faith. To look for meaning and purpose at the level of inanimate matter would be as unreasonable an act of faith as an attempt to “explain” the masterpieces of human genius as nothing but the outcome of economic interests or sexual frustration.

Citing 13th-century Persian poet and philosopher Rumi’s famous line — “the eye of the heart, which is seventy-fold and of which these two sensible eyes are only the gleaners” — Schumacher revisits the notion of perceiving with something other than the intellect:

The power of “the Eye of the Heart,” which produces insight, is vastly superior to the power of thought, which produces opinions.


This is the process of gaining adaequatio, of developing the instrument capable of seeing and thus understanding the truth that does not merely inform the mind but liberates the soul.


Ideas produce insight and understanding, and the world of ideas lies within us. The truth of ideas cannot be seen by the senses but only by that special instrument sometimes referred to as “the Eye of the Heart,” which, in a mysterious way, has the power of recognizing truth when confronted with it.

A Guide for the Perplexed is a magnificent read in its entirety, the kind that gives more every time, the more you bring to it upon each new rereading. Complement it with Schumacher on how to stop prioritizing goods over people, then revisit Alan Watts on becoming who you really are and John Locke on understanding and the folly of our borrowed opinions.

Published August 22, 2014




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