by Seth Brotherton

This article deals with the question that has perplexed the greatest minds for many centuries. It asks the question "Is the human soul immortal?" and if so, can it be proven from human reason alone? But, before we ask whether the human soul is immortal, we must first ask, "What is the human soul?"

The soul is defined as the "vital principal" or the principle of life. It is the first source of life in a living being. It is the thing that makes a living thing live. It is the primary constituent that separates living beings from non-living beings. With this in mind, it is evident that all living things have a soul, this includes animals and even plants. But, just as there are different grades of life, so there are different grades of souls. Plants have a vegetative life; therefore they have a vegetative soul. Animals have a sentient life, (which is life with the capabilities of sensing which includes the vegetative powers) therefore they have a sentient soul. Human beings have a rational life (which is life with the capabilities of reasoning, which also include the sentient and vegetative powers), therefore, they have a rational soul.

In order to answer this question fully we must give a more in-depth definition of life. The formal concept of life consist in that a substance have the natural power of intrinsically moving itself by which it perfects itself or at least conserves its own proper perfection. This does not apply to things such as rocks or water or dirt, therefore such things do not have souls. This definition obviously applies to men, because they grow in knowledge, strength, nutrition, and many other things, therefore human beings have souls. But, we have not answered the question whether we can distinguish the soul of a human being from the soul of an animal. We do so, because there is an extra grade of life that belongs to human beings, namely, the rational life. Rationality is certainly an extra grade of life because it helps a being perfect itself in a distinct way. Rationality allows us to seek and obtain our last end, i.e. happiness. By happiness we become the most perfect beings that we are destined to be. So, certainly rationality is an extra grade of life.

Meaning of the question -- Is the rational soul immaterial, in other words, do the exercise of its powers depend on the material that it is in?

Answer -- yes, the human soul is spiritual and, no, the exercise of its powers do not depend on the material that it is in.

Proofs --

Proof 1: From the operation and object of the soul

A. Things, which exercise their operations independently from material, have an existence independent from material.

B. Indeed, the rational soul acts independently from material

C. Therefore, the rational soul has an existence that is independent from material. But, an existence that is independent from material is spiritual. Therefore, the rational soul is spiritual.

Proof of 'A'-- Things exists inasmuch as they act. Therefore, if something acts independently from material, it exists independently from material.

Proof of 'B'-- The operations of the rational soul is composed of two basic faculties. The faculty of the intellect, and the faculty of the will. The object of the intellect is truth; the object of the will is the good. Now, a faculty and the object of that faculty must be of the same order, otherwise they could not be joined together. But Truth and Goodness are immaterial things, because they do not have a weight, mass, volume, color, shape, texture, or any material qualities whatsoever. Therefore the faculties of the soul are also immaterial.

Conclusion -- Therefore, the rational soul is immaterial.

Proof 2: From the Impossibility of a Thinking Matter

A. If the human soul is material then, matter is able to produce ideas, since the rational soul has ideas.

B. But, it is impossible that matter be able to produce ideas.

C. Therefore, the human soul is not material, but immaterial.

Proof of 'B' --Matter cannot produce what is more perfect than itself in some way. Ideas are more perfect than matter because ideas are universal, necessary, and immutable. Material is none of these things, and so cannot give these things to ideas. Therefore, it is impossible for matter to produce ideas.

Proof 3: From the Freedom of the Will

A. The will is free.

B. But all material is necessarily dominated and determined by the laws of physics.

C. Therefore the will is immaterial. Since, the will is a faculty of the rational soul, the rational soul is also immaterial and spiritual.

Furthermore, if our intellects are material, then we would not be able to predict the future. The senses are dependent on the here-and-now information that it is receiving, but since the intellect is immaterial it can transcend time.

Also, as Aristotle observes, the senses after strong stimulation, are incapable of registering the impressions of weaker stimuli for a certain period of time. For example, when you hear a loud bang, you may not be able to recognize fainter sounds. Or, when you glance at the sun it renders you blind to other things for a brief time. But, this is not so with the intellect, the opposite actually occurs. When we study Calculus, Algebra seems much easier to us. If the intellect were just another sense, as the materialist would have us believe, then this would not be the case.

Now, having said all this we are now prepared to turn to the principle question of this article.

Meaning of the question -- When the body stops living, does the principle of life, the soul also stop living, or does the human soul continue in existence independent from the human body without ever ceasing to exist.

Answer -- The human soul is immortal, that is, it continues forever in existence by its own nature, even when it is separated from the body. In order to prove this there are three types of proofs; metaphysical, psychological and moral.

Metaphysical Proof

There are two conceivable causes that would make the rational soul mortal; it might be itself intrinsically liable to decomposition; or it might be essentially dependent upon some other subject the decomposition of which would involve its own disappearance. The first supposition cannot be the case because the rational soul is immaterial and is not composed of parts into which it can be decomposed. The second supposition cannot be the case because the rational soul has already been proven to be spiritual and thus independent of the body, and so can continue in existence without the body. Therefore, the soul by its nature persists in existence to no end. Also, we know that God can, but would not annihilate a rational soul after death, because it would show unintelligence in that he would have created a being, which by nature endures forever but then destroy it later.

Another Metaphysical Proof

Truth and the Intellect, and Goodness and the Will are of the same genus, because they are complementary things, just as perfection and perfectible are of the same genus.

Indeed, Truth inasmuch as it is Truth is necessary and incorruptible, and likewise the object of the will is necessary and incorruptible.

Therefore, it is necessary that the intellect and will be incorruptible also.

Psychological Proof

All intellectual natures desire to live always, since every being tends to its own perfection and unending life is a perfection.

But, natural desires are not frustrated. If they were frustrated then it would be an effect of an unwise, inconsistent, and torturous God.

But, God is none of these things, therefore, all intellectual natures, e.g. rational souls, live forever.

Moral Proof

If rational souls did not persist in existence, then good men would not be able to be rewarded, and evil men would not be able to be punished.

But, we know that God rewards the good and punishes the evil because He is just. But a requisite of punishment or reward is persistence after death.

Therefore, the rational souls continue to exist after death.

Seth Brotherton

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