Quaestio Disputata on the Soul

Quaestio Disputata on the Soul

Quaestio Disputata on the Soul


ARTICLE 1: Whether the soul exists?

CONCLUSION: "Living material things possess a soul that makes their matter be actually alive."

NOTIONS.  Soul is defined as the substantial form of a living body, or that in a living body which makes the matter (which of itself is only potentially alive) be actually alive.  Organic unity is the unity that is proper to organisms, that is, to living things.  Plants and animals, including man, possess a unity that is very distinct from the unity of inanimate objects, such as a rock, the air, or a computer: the parts of inanimate objects are merely juxtaposed, that is, placed locally next to each other; if they work together toward some end, it is only because their harmony has been imposed by some extrinsic agent.  Unlike living things, inanimate objects do not possess a natural, intrinsic unity that orders all their parts toward the same end.  Organic unity is ultimately explained by the presence of a soul.  An organ is any part of a living body that is unified (with partial or relative organic unity) for the sake of one function.  Hence, for example, all the parts of the heart are ordered to the function of circulating blood in the body; all the parts of the stomach are ordered to the function of digesting food; etc.  But it should be noted here that "organ" is not said strictly, as biologists and anatomists use the term, i.e., as distinguished from cells and tissues (which are the components of organs) on the one hand, and from systems (which are composed of organs) on the other.  Rather, it is meant more broadly, to refer to any part of the body that is in some way unified: thus, any part of the body, no matter how simple or complex, that has some degree of relative organic unity--e.g., cells, tissues, and systems--could be termed an "organ."

POSITIVE PROOF.  1st Argument: From the Proper Theological Sources (loci theologici).  It is clear from the explicit testimony of the sources of revelation (both Sacred Scripture and the witnesses and monuments of Sacred Tradition, including the consensus of the Fathers, the consensus of Theologians, and the consensus of the Faithful) that human beings have souls.  This teaching is, therefore, de fide and its denial would amount to heresy.  Refer to a dogmatic manual (e.g., Tanquerey or Ott, which have been translated into English) for the positive sources.  The Council of Vienna further defined the dogma that the soul is essentially and per se the form of the body (Dz 481).  It should be noted, however, that the existence of souls in brutes (i.e., irrational animals and plants) is not de fide; it is, rather, a sententia communis, that is, a teaching that is unanimous among theologians who discuss the subject.

2nd Argument: From the Extraneous Theological Sources: Practically all thinkers of the philosophia perennis, in particular all of its major exponents, such as Plato, Aristotle, Augustine, and Aquinas, as well as all scholastic philosophers, are unanimous in upholding the existence of a soul--that is, of an immaterial principle of life--in all living things, including brutes.  This tradition generally distinguishes between three genera of souls: vegetative souls, sensitive souls, and rational souls.  The mechanist trend of denying the existence of the souls of brutes began in modern times and was popularized with Descartes.

SCHOLASTIC PROOF.  1st Argument.  If all that is necessary for something to be alive is that it has matter, then all material things would be alive.  But not all material things are alive.  Therefore the conclusion follows.  Confirmation of the Major Premise.  If matter were a necessary and sufficient condition for life to occur in a body (i.e., a corporeal substance), then the inevitable result would be that all things that satisfy that condition--that is to say, all things that possess matter--would be alive.  Confirmation of the Minor Premise.  This is directly verifiable through experience: there are things like chairs and pencils, which are material but are not alive.  A Difficulty.  The argument proves that the antecedent of the major premise is false; that is to say, it proves that it is false that "all that is necessary for something to be alive is that it has matter."  But it does not prove the conclusion of the article, namely, that "living material things possess a soul that makes their matter be actually alive."  Resolution of the Difficulty.  If matter is not sufficient for something to be alive, this means that some immaterial principle is required to make something potentially endowed with life be actually alive.  For the sake of brevity, we give the term "soul" to this immaterial principle that is required to make a body potentially endowed with life be actually alive.

2nd Argument.  If every material organ in the body of a living thing receives its organic unity from outside itself, then there must ultimately be something that is not a material organ that imparts organic unity to all the organs.  But every material organ in the body receives its organic unity from outside itself.  Therefore, the conclusion follows.  Confirmation of the Major Premise.  Every material organ in the body has a relative organic unity: although it is subordinated to the end of the whole body, it is one entity insofar as all its parts are ordered to the same function in the body.  Now, the question is whence does the organic unity come.  It cannot come from the organ itself, as shall be shown below.  Hence, it must come from outside the organ.  Now, if it comes from outside the organ, it can either come from another organ, or from something that is not an organ.  If it comes from an organ, then the question arises again concerning the organic unity of that organ, and so we end up with an infinite regress. Therefore, ultimately we must reach a source of organic unity that is not a material organ.  Confirmation of the Minor Premise.  The minor must be true, because its contradictory ("every material organ in the body of a living thing receives its organic unity from within itself") is absurd.  If every material organ in the body of a living thing received its organic unity from within itself, then it would have to give itself organic unity before it possessed organic unity, which would mean that it would have to exist as a unified organ before it becomes a unified organ.  But this would be absurd.  Therefore, the contradictory antecedent results: every material organ in the body of a living thing receives organic unity from outside itself.  A Difficulty.  This argument proves only the ultimate source of organic unity is not a material organ; but it does not prove that the ultimate source of organic unity is immaterial.  The source of organic unity could be something that is not an organ, but that is nonetheless material.  Resolution of the Difficulty.  If the source of organic unity is not a material organ, then that leaves only three logical possibilities: it is either (a) an immaterial organor, or (b) a material non-organ, that is to say, a body that is not an organ, or or (c) an immaterial non-organ.  Now, (a) cannot be, for it is a contradiction: "organ" signifies a material entity, as defined above, and hence there cannot be an immaterial organ.  Also, (b) cannot be an ultimate source of organic unity, because insofar as it is a material entity that has some unity, it itself requires a source of unity--and it cannot give itself unity, for the reason that we discussed above.  So only the third logical possibility (c) is a real possibility.  Therefore, the ultimate source of organic unity is an immaterial non-organ: that is to say, an immaterial principle.

OBJECTIONS.  1st Objection.  If a simpler explanation is available, then one ought to prefer it over all other explanations.  Now, a simpler explanation is available for the life of living things--namely, that matter and the laws of physics conspire to form life, without the aid of any immaterial principle.  Therefore, one ought to prefer this explanation to all others.  Reply to the 1st Objection.  Distinction of the Major Premise.  I concede that if a simpler explanation is available that satisfactorily explains a phenomenon through its first causes, then one ought to prefer it over all others.  But I deny that if a simpler explanation is available simply speaking, then one ought to prefer it over all others.  Contradistinction of the Minor Premise.  I concede that a simpler explanation, simply speaking, is available for the life of living things--one that has recourse only to the laws of physics and appeals to no immaterial principle.  But I deny that this explanation satisfactorily explains the phenomenon of life through its first causes, for it ignores the issue of whence organic unity arises, and even the existence itself of organic unity.  And I deny the objector's conclusion.

2nd Objection.  Regarding natural things one ought not to reach conclusions that are not empirically verifiable.  But the conclusion of the article is not empirically verifiable.  Therefore, one ought not to accept such a conclusion.  Reply to the 2nd Objection.  Distinction of the Major Premise.  I concede that concerning natural things one ought not to reach conclusions that are not empirically verifiable in any way whatsoever.  But I deny that regarding natural things one ought not to reach conclusions that are not directly empirically verifiable.  As a matter of fact, the major premise itself is not directly empirically verifiable.  Hence, if the premise pretends to affirm that we ought not to reach conclusions that are not directly empirically verifiable, then the premise is self-refuting.  Contradistinction of the Minor Premise.  I concede that the conclusion of the article, that the soul exists, is not directly empirically verifiable, for the soul is neither visible, nor tangible, nor can be perceived directly through any of the exterior senses.  But I deny that the conclusion of the article is not empirically verifiable in any way whatsoever, for the existence of the soul is indirectly empirically verifiable, that is, through its effects, namely life and all its properties, such as organic unity, nutrition, reproduction, self-guided locomotion, sensation, the appetites, reason, and will, which are themselves directly empirically verifiable.  And I deny the objector's conclusion.

3rd Objection: One ought not unnecessarily multiply principles. But positing an immaterial act/form (i.e., soul) to explain living things unnecessarily multiplies principles. Therefore, etc.  Explanation of the minor: One can satisfactorily account for the difference between living things and nonliving things in terms of the complexity of living things: living things are more complex arrangements of the same matter of which nonliving things are composed. Therefore, living things can be explained in purely material terms. Therefore appealing to an immaterial principle is superfluous.  Reply to the 3rd Objection.  I concede the major, but I deny the minor.  If one cannot satisfactorily explain life without an immaterial principle, then positing such an immaterial principle is not unnecessary.  But, as was shown above in the first argument, one cannot satisfactorily explain life without an immaterial principle.  Therefore, positing an immaterial principle of life is not unnecessary.

ARTICLE 2: Whether the souls of brutes are immaterial?

CONCLUSION: "The souls of brutes are immaterial, i.e., they are not made out of matter."

NOTIONS. 'Immaterial' and 'spiritual' are not synonymous. 'Immaterial' can have two meanings: (a) not made out of matter, and (b) having an act that is completely independent from matter. Only the second sense can be said to be synonymous with 'spiritual'.  Now, whatever is 'immaterial' in the second sense (i.e., spiritual) is also 'immaterial' in the first sense, but not vice versa. In other words, whatever has an act that is completely independent from matter must not be made out of matter. But there can be something that is (a) made out of matter, but that is not (b) independent from matter (or 'spiritual'). Such is the case with the souls of brutes--indeed, all forms, not only souls, are immaterial in this sense, insofar as they are not the matter that they inform. But human souls, angels, and God, in addition to being 'immaterial' in this first sense, are also 'immaterial' in the second sense, that is, having an act that is completely independent from matter (= 'spiritual') and for this reason they alone are said to be 'subsistent'.

ARGUMENTS. 1st Argument.  Whatever is not made out of matter is immaterial. But the souls of brutes are not made out of matter. Therefore.  Proof of the Major: Being material means being made out of matter. Being immaterial means not being made out of matter. These two are mutually exclusive, jointly exhaustive species, such that given an entity, it must be either immaterial or material.  Proof of the Minor: The souls of brutes cannot possibly be made out of matter, because living matter cannot of itself live; rather, matter requires a formal principle outside of itself that makes the matter live actually. Now, if that formal principle is itself material, then it would require some formal principle outside of itself to live. And then we would have an infinite regress. Therefore, the process must have an end: a first principle of life that is not itself material.

OBJECTION. If the souls of brutes are immaterial, then they are subsistent, i.e., that they do not survive death. But, as St. Thomas teaches, the souls of brutes are not subsistent. Therefore, the souls of brutes are not immaterial.  Reply. I concede the minor. I distinguish the major. I concede that if the souls of brutes were immaterial, or "spiritual," in the sense that they have an immaterial act that is completely independent from matter, then they would be subsistent. But I deny that if the souls of brutes are immaterial, in the sense that they are not made out of matter, then it follows that they are subsistent. And I deny the objection's conclusion.

Only the rational soul has an act that is completely independent of matter, for the acts of the intellectual power are not the acts of any bodily organ.  For this reason the rational soul is both material (i.e., not made out of matter) and spiritual or subsistent .  All the acts of the souls of brutes, however, are acts of bodily organs, and therefore depend upon matter.  For this reason the souls of brutes are not spiritual or subsistent, even though they are immaterial.  Both souls are immaterial but only the rational soul is spiritual and subsistent.

Article 3: Whether the soul and the body are substances

ARGUMENT.  If the soul and the body were each a substance, then each could exist independently of the other.  But the body cannot exist independently of the soul.  Therefore.

Proof of the Major.
Proof of the Minor.


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Copyright © 2009 Francisco J. Romero Carrasquillo, PhD.  All rights reserved.