Esse and Essence in Regards to Technology

From the Bring Back Reason series.

St. Thomas Aquinas advanced our understanding of the science of metaphysics by recognizing that the most fundamental distinction, more fundamental than the distinction between act and potency, is the distinction between esse and essence. Esse, the being of a thing, relates to essence, what a thing is, its nature, as act to potency. Esse can be thought of as a thing’s act of existence. Rather than simply the minimal perfection of existence to which other perfections adhere, esse is the source of all a thing’s perfections, of the entire actuality of a thing. A thing is true, good, and beautiful to the extent that it has esse. But since esse is received by an essence, it is limited. The essence or nature of a thing determines it to be a thing of a particular kind. Only God is pure esse, existing as full actuality without any hint of potency. On the contrary, pure potency cannot actually exist, since it would be pure “can be” and lack all “is.”

It is accurate to say that a particular thing has more or less esse than another thing. The thing with more esse has a higher level of perfection. The lowest ontological order is that of “mineral.” All non-living material substances fall into the category of mineral. So not only would a particular rock or piece of metal be a mineral but a substance like water would also be on this level. Machines are basically combinations of mineral substances arranged in specific ways for functional purposes. A simple machine like a gardening hoe is a combination of a handle, perhaps made from wood or another synthetic material, combined with a metal piece designed for effectively moving soil in a way that helps the gardener prepare the soil for planting. A smart phone is a complex machine with intricate parts made from various metals and plastics that enable the device to receive and present information in various ways.

The next ontological level of being is called “plant.” A plant differs from a mineral specifically in that it is “alive” while the mineral is “inanimate.” As a living thing a plant is a naturally organized body that possesses within itself its own principle of self-perfective motion. The acorn is received into fertile soil and develops organically into the mighty oak tree. All of the biological functions of the oak tree serve to support and further its growth into the mature tree that is the fulfillment of its essence. When its branches spread wide toward the sun and its roots sink deep into the soil it is actively reaching for what it needs to flourish as an organism. Indeed the only way to “turn off” this active seeking for its own good is to kill the tree. When the tree dies sap no longer flows through the branches and the wood is inanimate, like other minerals.

Contrast this ontologically higher level of existence with the functions of the smart phone. The capabilities of a complex machine like the smart phone are quite significant but there is no organic unity to the phone. Its integrated functionality is something imposed upon the device by the plan of the persons who designed it. Unlike the tree, the smart phone can be completely turned off without damaging what it is. The tree can never cease being in act. It simply has more esse than anything on the level of mineral. So long as it is alive it contains a level of perfection higher than that of the phone.

The next ontological level is that of animal. Animals are not only alive but are sentient beings. A plant cannot “feel” in the same way an animal can. A squirrel goes about its search for nuts, storing up food for the winter, with a higher level of awareness than the tree that sinks its roots deep into the soil. Likewise the squirrel is able to do such things as recognize and avoid danger and seek a mate. The emotional life of a dog seems to be even higher. Anyone who has a pet dog should be amazed at the way the dog is loyal to its master and naturally seeks to defend its human “family,” exercising a sense of responsibility. Dogs even appear to dream when sleeping.

Higher still is the level of humans, which add to the sentient life of animals the specific capacity of reason. Aristotle defined man as a “rational animal.” And even higher still are angels, pure intellectual substances that are not limited by matter.

As we advance up to higher levels we are encountering beings with increasingly more esse, a higher act of being. In each case the esse is received into a higher essence as well. But the perfection of a thing is specifically rooted in its esse, which is its act of existence and the source of all its perfections. A dog’s fairly rich sentient life is a greater perfection than the life of an oak tree specifically because the dog has more esse than the oak tree. Again, it is important to realize that ontologically the existence of a thing is not the mere baseline perfection to which other perfections are added in higher things. Rather the higher things have more perfection because they have more being, more esse.

Even angels, however, though pure intellectual spirits, are limited by their essences. In an angel its esse is still received into an essence (a unique essence to each angel since otherwise there would be nothing to distinguish one angel from another). Only in God do we have pure esse, pure act of existence that is in no way limited by essence. St. Thomas Aquinas is thus famously able to assert that God’s essence is his esse. Only God is pure esse, pure act without the slightest limitation of potency. It is significant that God revealed his name to Moses at the burning bush as “I Am Who Am” or “I Am Existence” or “I Am Esse.”

What does this mean for how we should view technology?

Technology is a part of contemporary life in a way that previous generations could not even imagine. We have machines for transportation such as cars, trains and airplanes that far surpass what was possible for people of former times. Computer technology puts information and connectivity in near constant reach. Machines are able to do many things that formerly were only possible through great human effort, if at all.

The first point that should be made is that these technological advances are fundamentally good and can be used in the service of humanity. Even people who are generally skeptical about technology recognize that advances in medical science, for example, really do help people. No reasonable person would advocate for allowing a person to suffer a painful death from an illness that can be easily cured by modern medicine.

Even so, most people recognize that the power that technology places in the hands of people of our time is potentially dangerous. The same technology that can be used to cure can also be put to use in the development of biological weapons and the same nuclear technology that can produce needed energy can also be used in an atomic bomb.

A specific contribution of realism is that realism can help people understand in a more fundamental way what nature is and what technology is as well. If we see the world properly we will have a sanity that will not only allow us to flourish as human beings but also make it more likely that we will use technology properly, in a humane way. We have already discussed the importance of the difference between a living thing and a machine. We will better appreciate what technology is and what nature is if we internalize the intellectual habit of recalling that the simplest plant is in act in a more profound way than the most advanced computer.

On the other hand, the failure to see the richness of the being that is manifest to us in nature leads one to see nature in an overly mechanical way. It may be difficult to find someone who will not acknowledge a difference between a living thing and a machine if pressed, but there are many who look at nature and the world with eyes that are “partly closed.” They see knowing how something functions as primary, rather than first trying to know what it is. Many people have unfortunately fallen out of the habit of first seeing and appreciating what exists. Their gaze does not dwell on the whole of the thing before them but immediately moves to discerning the parts and how these parts interact and function. Granted, as stewards of nature we need to try to understand how things function so as to properly govern the world and order creation toward human flourishing. The problem is that, without a gaze that seeks first what is rather than how things can be manipulated, we become blind as to how we should appropriately intervene. Our efforts to exercise control over nature do not respect what nature is and so end up easily working against the inherent ends of things. We intervene in a way that hinders things from reaching their proper ends rather than assisting them. We should not strive to exercise unlimited control over nature but should look to nature for standards of perfection to guide us.

Michael Moynihan

About the author:

Michael Moynihan


A native of Rochester, NY, Michael Moynihan earned B.A. degrees in history and science pre-professional studies with a concentration in the Honors Program from the University of Notre Dame. He graduated Summa Cum Laude and was a member of Phi Beta Kappa. After teaching for one year and earning a master’s degree in theology from The Catholic University of America, he joined the faculty of The Heights School in 1995. He has taught chemistry, Advanced Placement chemistry, eighth grade science, ethics, math and religion, has coached The Heights’ cross-country team and founded The Heights Mountaineers program. Michael was named Head of the Upper School in 2002. He and his wife, Angela, have eleven children, with four sons here at the School.

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