First off, do plant and animal souls even exist? A scientific examination can answer this question, but I’m not so sure it’s accurate. A strictly biological investigation seems to answer the question, What is life? rather than What is a soul or principle of life? According to "History of Life through Time" (Regents of the University of California, 2008), it appears that life on our planet began around 3.7 billion years ago, the origin of life might be a good place to start.
Some scientists believe that over billions of years, pre-biotic environmental conditions on Earth were such that ongoing evolutionary adaptation resulted in the formation of an extremely basic cell. Aleksandr Oparin suggested in his book, The Origin of Life on Earth (1938) that from a primordial soup of organic molecules in an atmosphere of hydrogen, not oxygen, the first cells spontaneously formed in the lakes and seas of the Earth as it cooled. The cells that survived had developed the ability to reproduce.
However, astrophysicist Paul Davies doubts this entire theory. “Because even the simplest living cell is immensely complex, the odds of such a thing forming by chance are virtually zero” ("Living with Aliens" in The Guardian, 2005). He feels that some sort of life principle is at work guiding matter to reach a living state Davies’ opponents are quick to point out that the odds, however small, are not actually zero. Theoretically, all it took was just one occasion!
Being Alive Scientifically
Although there are many variations on this theme, the critical attributes of being alive on planet Earth are usually described by scientists from a biological standpoint. Some non-living creatures possess one or several of the attributes discussed below, but not all of them.
Gelderblom's "Structure and Classification of Viruses" (Medical Microbiology, 1996) says that all living things except viruses are made up of tiny cells. Where amoeba and paramecium consist of a single cell, a horse, a tree, a human being consists of trillions of cells.
Regardless of size, living organisms are ordered not only at the cellular level, but also at the molecular level. Here, creatures are structured by tissues, organs, and systems (digestion, circulation, nervous, lymph) which are in themselves organized, but all these unique systems are so structured as to preserve the integrity of the total being: a mouse, a tulip, a planaria, a human, an amoeba. "Life" (New World Encyclopedia, 2009) claims the following ordering principles for living things.
1. Living things have a common basic chemistry: They are water and carbon based.
2. As a living creature grows in size, it develops more fully and begins to age.
3. To ensure survival, a living thing is able to maintain a balance within its individual parts and systems.
4. Living things reproduce themselves.
5. Living beings respond in some way to environmental stimuli.
6.In order to keep on existing, a living being must interact with its environment for energy to maintain its own internal organization, to grow, and to reproduce.
7. Organisms are able to adapt to the environment within certain limits.
Being Alive and a Principle of Life
In my mind, as admirable as this scientific list may seem, something seems to be lacking. Although it lists the ability to maintain a balance—homeostasis—among these attributes as a key element for survival, it does not explain what this ability really is. Wherein does it lie within the paramecium’s single cell? Where is it in the trillions of trillions of cells making up a giant oak or pine tree? Although it appears to be localized within the head or brain area of larger animals, where is it in planaria or amoeba?
But if the organization principle lies within every single cell of the living entity, still, what tells the oak tree as a whole when to make a root, a branch, a twig, a leaf? Certainly, it needs to maintain its balance, but what guides it to do so? What tells the tree that at a certain distance up its trunk a new branch should form here and not in another spot?
Furthermore, what tells the one-celled amoeba it is time to divide? What tells the eyeless single-celled paramecium to turn its body so it can pull in bacteria through a slit in its one side? What tells it to want to eat at all? Something oversees its desire to survive.
Farther up the developmental ladder are humans. Wherein is hidden the principle in human conception that tells two united sex cells when to divide and eventually form a zygote, an embryo, a fetus, a child? What’s more, was each half of this homeostatic ability within each parent’s egg cell or sperm cell?
The answer to these open-ended questions suggests that every sperm cell and every egg cell has the ability to join with its opposite in such a way that a guiding principle is passed on in this union.
Looking at all these questions seems to me to point to some kind of principle of life existing along with a living being that keeps it organized. Is it material? Is it spiritual and immaterial? Is it something paranormal? Is this what people commonly refer to as the soul? It seems that a number of scholars down through the ages agree with this idea even though modern biologists do not.
Aristotle’s Animal Soul
In 350 B.C.E., Aristotle (On The Soul) philosophizes about the nature of the soul. He claims that all existing things, including living organisms, consist of substance with a determining form. This substance has already trespassed from mere possible being because its form has given it reality. Thus, he claims the soul is that organizing factor which gives a natural body its organized, living actuality.
Therefore, a plant has a soul. It contains a factor that manages the plant and keeps it functioning as a whole. It oversees the plant’s growth and reproduction cycle. Aristotle likened the simple organs of a plant to those of more complicated animals. The roots of a plant, he claimed, are like the mouth of a higher functioning animal. Both are used to obtain food.
The Islamic Animal Soul
In his treatise An-Nafs (The Soul), the Islamic Philosopher Ibn Sina (980-1037) explains that because we observe a living body acting a certain way, it is its action that prods us to infer that each living body has a soul. For example, when we see an animal reproducing, eating, moving and perceiving, we can infer that these actions come from some principle within the animal. A cow grazes, pulling up grass for nourishment. Unlike a rock, or a dead cow for that matter, this ingestion of food, according to Sina, is indicative of an animal soul.
Similarly, when we see a pine tree getting taller and producing cones for regeneration, we can infer from these actions that the tree has a plant soul. Its soul is more limited than an animal soul. Animals have locomotion and perception of the outside world.
Another Islamic thinker, Ibn Rushd (circa 1180), claims in Tahafut Al-tahafut (The Incoherence of the Incoherence, trans. S. Van Den Bergh, 1954) that the animal soul even has a form of imagination. He says that when a sheep has a notion that a wolf is to be avoided, the animal is using this power of its soul.
The Medieval Animal Soul
Following in the tradition of Thomas Acquinas (1225-1274), the Scholastics of the Middle Ages held almost the same views about the souls of plants and animals as did Aristotle. They believed that the origin of animal life is the soul, which is superior to the plant soul only capable of nutrition, growth, and reproduction.
Acquinas posited that the animal soul is sensitive. It is capable of perception of reality, motion, and an additional quality named appetition (Summa Theologica: Rational Psychology). Because of this quality in its soul, an animal is able to strive toward things it finds desirable and avoid what is not. This quality is reminiscent of Ibn Rushd’s notion mentioned above. A bird, for example, will not hunt just any food. It will seek the kind of food that it finds most desirable and suitable for its beak (a finch's bill versus that of a duck or sandpiper). In many ways, this sounds like what modern biologists refer to as instinct.
Descartes and the Animal Machine
Because of his mind-body dualistic philosophy, Descartes attributes no real mental functions to animals. To him, it is scientifically ridiculous to claim they have souls. Animals are nothing more than complicated machines which operate according to instinct. He quarreled with the ancients from a Catholic Christian point of view.
To Descartes, an animal that had even the simplest of thought processes would have to have an immortal soul ("Animal Soul," Encyclopedia of Philosophy, 1967). Why? He believed that the psychology of his time combined both a psychological and a theological concept of immortal soul which could never be separated. They were one and the same. To claim an animal had a soul was an untenable position within Catholic dogma. Descartes felt it improper to believe animals have souls like humans; if that is so, he believed that man would have nothing different to hope for in an afterlife than the insects of the Earth have.”
Modern Science’s Animal Soul
Today, it would seem that science views the idea of any soul or principle of life — whether human or animal or plant — as sheer religious or philosophical nonsense. Differences between the intelligence and reasoning abilities of animals and humans, is seen as a matter of degree. It is well known that scientists who have worked with chimps have been able to teach these animals a multitude of signs which they use for communication.
Recently, I attended a fascinating lecture given by Jane Goodall (March 25, 2009) who spent over forty years studying chimpanzee behavior in the Gombe Game Reserve in Africa. After her talk, she answered many questions. When asked about chimpanzee intelligence and behavior, she acknowledged that chimps’ behaviors are extremely complex. They are capable of maintaining emotional relationships and can make use of tools. However, she stated that they should not be kept as pets and that humans should never forget that they are wild animals.
At the human level, MRI scans have localized portions of the human brain that seem to become activated when various types of thinking takes place, especially emotions. Thus, modern reductionistic thinking suggests it is only a matter of time with the proper sophisticated equipment, that what used to be considered as a principle of life or soul will ultimately be traced to activity within the grey wrinkled brain inside the skull. Here, it is believed that the neurons, both as single cells and as independent networks of cells, work together to produce all the higher functions that people typically refer to as the mind or the soul (Astonishing Hypothesis: The Scientific Search for the Soul, Francis Crick, 1994).
On a much more personal level, scientist Warren Brown upholds a theory of "Nonreductive Physicalism and Soul" (American Behavioral Scientist, 2002) that abandons both the body-soul dualism of theological anthropology along with absolute reductionism of modern science. Brown argues that many of the traditional capacities that once were assigned to the soul such as human nature and human experience are now seen as emergent functions of the brain; for example, qualities such as emotion, morality, free will, reasoning, spirituality.
Personal Thoughts about Animal Souls
I am not an advocate of spiritual souls in any kind of religious sense. I do believe that there is some kind of organizing principle that manages the life of a plant, an animal, or me. Maybe consciousness is responsible in me, but that seems an unlikely solution for animals and particularly plants which have no brain or noticeable nervous system.
I don’t think living organisms can be defined by a descriptive write-up of their component parts and then a summation of those parts. I can examine and describe a sheet of paper lying here on my desk. That would be a simple task. But if that paper stood up and began walking across my computer keypad then dipped one of its ends into my coffee for a drink, I would have to define that 8.5" by 11" sheet using highly different vocabulary which might be more subjective than objective. Science may someday find this illusive organizing principle, but until then, I’m satisfied to sit back and wonder at the mystery of it all. The following two short stories are part of this enigma.
The Killdeer Soul
Not long ago, I walked through some high grass in an open area of a nearby cemetery. I noticed a bird about fifteen feet away flopping about as if it were injured. As I approached the poor thing, the bird recovered somewhat and walked another ten feet or so dragging its wing. Not wanting to frighten it, I snuck closer and closer, but the bird eyed me carefully and again walked some distance away. This behavior continued until the animal suddenly took flight and turned back toward the area where I first encountered it.
From a search on the Internet, I found that this display of injury was an instinctual behavior of a killdeer bird to lead prey away from its nest. The nest is usually built on the ground in weedy and/or grassy areas an must always be protected. Science would call this an instinctual display, but it made me wonder where this urge to preserve its young came from in the killdeer. Was it also in the eggs the bird had laid several days ago?
An Elm Tree's Soul
Last week, I called a tree expert to examine an elm in by backyard. The tree barely had any leaves on its many towering branches. But it did have a multitude of weak, twig-like shoots bearing small leaves, which began to appear all over the tree's trunk. The tree expert explained that the tree had Dutch Elm Disease. It was in its final stages of life.
When I asked how he knew that, he said that all the small twig-like branches sprouting on its trunk grew instinctively as a last resort to produce enough chlorophyll to save the tree. This happened because of the lack of chlorophyll from the very sparse upper leaves. Bark beetles had infested the elm and prevented the downward flow of nutrients that normally photosynthesized in the elm's myriad leaves.
Neither the tree expert nor any information I could find explained how the elm tree knew it was dying and needed to sprout the small, life saving, twig-like branches and leaves on its trunk. Some organizing principle within that tree told it to do so.
I must admit I have a great respect, love actually, for all living creatures because the enigma of life, or the principle of life, or whatever it is that organizes being is a breathtaking mystery. Every time I walk in the woods, especially when I see wild animals, I sense it. So, let's have a hearty round of applause for plant and animal souls. Charles Darwin summed it best: “The love for all living creatures is the most noble attribute of man.”