Listers, today we are going to take a look into Sacred Tradition and explore the reality of the soul. The following is a basic introduction, and will serve as a foundation for further discussions. All quotes – unless otherwise specified – are taken from our beloved Angelic Doctor and his Summa Prima Pars Q75A1.
Is the Soul a Body?
No, the soul “is simple in comparison with the body, inasmuch as it does not occupy space by its bulk.” – St. Augustine, De. Trin vi 6. Whereas bodies are complicated with such traits as weight and dimensions, the soul is not.
What Is the Soul?
The soul is “the first principle of life in those things which live: for we call living things animate, and those things which have no life, inanimate.” In Latin, soul is anima, from which we derive our words animate and inanimate. Things that have life are animated; thus, they have an anima or soul.
Do Plants and Animals Have Souls?
Life “is shown principally by two actions: knowledge and movement.” Plants and animals are animated beings that respectively display knowledge and movement. Where there is life, there must be a soul; thus, yes, plants and animals have souls.
Is Every Principle of Vital Action a Soul?
“It is manifest that not every principle of vital action is a soul, for then the eye would be a soul, as it is a principle of vision; and the same might be applied to the other instruments of the soul: but it is the first principle of life, which we call the soul.”
How Can We Articulate This “First Principle of Life?”
Plants and Animals (including the Rational Animal: Man) are composite beings – they are composed of matter and form. We know matter never exists without form, e.g., wood must always be in the form of a tree, chair, table, etc., it can never be some formless woodness. Matter – since it cannot exist on its own – is in potential to form; or rather, we may say that the form is the act and matter is the potency. Without form, the matter does not exist.
Now, animated – ensouled – beings differ in their articulation of matter and form. Our form is not our external dimensions, but rather the “first principle of life” – the soul. The soul is the form of the body. It is the act that gives life.
“Therefore the soul, which is the first principle of life, is not a body, but the act of a body.”
For further reading, see SPL on Matter & Form.
Are All Souls Immortal?
No, they are not. Though the purview of the Catholic tradition allows for the belief of Plant (Vegetative) and Animal (Sensitive) souls, it is clear that only the souls of humanity are made in the Imago Dei and bear immortality. Plant and Animal Souls also differ in their respective powers from each other and from the Rational Soul of man.
Plants and Animals return to dust at death, while the immortal soul of man is ultimately bound to either heaven or hell.