Listers, today we continue our study of the soul by delving deeper into the Vegetative Soul or Plant Soul. The following quotes are taken from Gilson’s Christian Philosophy of St. Thomas Aquinas. Gilson is primarily a historian and a philosopher second. He is adequate for certain Thomistic principles, but overall I would suggest Listers look into such giants as Ralph McInerny or Fr. Garrigou-Lagrange.

1. What Is a Soul?

“In its wide sense, soul is defined as the first act of an organized body capable of performing the functions of life;” thus, “like all form, a soul is an act.” The soul is the form of a body. It is the first principle of life. In Latin, the soul is the anima which animates the body. Where there is life, there is a soul.

Read More:
SPL on Matter & Form
SPL on The Soul

2. What Are the Different Types of Souls?

Three Types: Vegetative, Sensitive, and Rational Souls

Vegetative: “At the bottom we find a power of the soul whose one object is the body to which it is united,” and “the vegetative soul only acts on its own body.” The Vegetative Soul is the soul of plants.

Sensitive: “There is another genus of powers of the soul corresponding to a more universal object, namely, to all sensible bodies, and not merely to the one sensible body with which the soul is united.” The Sensitive Soul is the soul of animals. They possess many powers that plants do not, e.g., the five senses and a type of memory.

Rational: “Above these, there is a power of the soul with a still more universal object; that is, not merely sensible bodies in general, but all being taken in its universality.” The Ration Soul is the soul of man. It alone is made in the Imago Dei, and has immortality and rationality.¹

3. What Does Powers of the Soul Mean?

As the first principle of life, the soul is the seat for certain vital functions. These functions or powers of the soul have particular actions, which can be determined and separated according to their objects.

“Thus actions and the powers from which they come are distinguished from on another by their objects.”

"Cannibal Tree" - A tree grown around a sawed off stump Wikicommons Jan Tik

4. What Are the Powers of the Vegetative Soul?

Overall, the Vegetative Soul must be able to provide the basic powers of life demonstrated by plants. The plants ability to nourish itself, grow, or even begin the miracle of life are all powers rooted in the first principle of life - the soul.

Vegetative Power: “The body considered as receiving the life of the soul which informs it.” The Vegetative Power imports three distinct powers: generative, augmentative, and nutritive.

The Threefold Division of Power within the Vegetative Soul

Generative Power: “By the first of these operation the body receives actual existence.”

Augmentative Power: “At the beginning of their existence they have only imperfect being as far as quantity is concerned. For them there must be, besides the generative powers, an augmentative power, through which they achieve their proper natural state.” The Augmentative Power is what allows and governs living organisms to move from a nascent state to mature one. In the case of plants, they move from a seed to a mature plant.

Nutritive Power: If the soul contains the ability to govern itself growth from nascent to mature, it must also have a way to nourish itself. “The very conservation of the individual demands a nutritive power to restore continually what it has lost, and to bring to it what it needs if it is to attain its perfection of stature, as well as what it needs to produce the seeds necessary for its own reproduction.”

“Thus the vegetative power itself supposes a generative power which confers being, an augmentative power which confers fitting stature, and a nutritive power which preserves it in existence and in its own proper quality.”

5. Do Other Souls Have These Powers?

Does not the Sensitive Soul of animals and the Rational Soul of man have augmentative and nutritive powers? Do we not grow and receive nourishment? Yes. In studying the three types of souls, one can see the principle that the higher orders and perfects the lower. The Sensitive Soul will take up the powers of the Vegetative and the Rational Soul will take up the powers of both. In certain cases, a perfection happens and the power that resides in the lower soul actually differs from the same power in a higher soul, e.g., the memory displayed by animals and the memory displayed by rational animals.

1. Catholic Druidism: Dear Listers, to avoid any accusations that we here at SPL are actually quasi-Catholic-druids and not faithful students of St. Thomas Aquinas, let us clearly state – once again – that the souls of plants and animals are mortal, they return to the dust, and only the rational soul of man bears immortality and the Imago Dei. [↩]