Over lunch on Sunday, Brian B asked me to explain my disagreement with Ed Feser and others over Aquinas’ hylomorphism. Here is a pithier statement than the ones I’ve already posted.
I will assume with Aquinas that human beings after death continue to exist as disembodied souls until the general resurrection. The question I and others have posed is how the persistence of individual souls after death is conceivable on the Aristotelian hylomorphic principles to which Thomas subscribes. Why should this be a problem? The problem is that the following propositions, each of which is a doctrinal commitment of Thomas, are collectively logically inconsistent: they cannot all be true.
a) Designated matter in material substances both individuates their forms and accounts for the substances’ numerical difference. Thus Peter and Paul are two and not one because of the difference in their designated matter. And their forms are individuated by designated matter as well. This implies that (i) Peter’s substantial form is numerically different from Paul’s, and that (ii) neither form is an individual form without the matter that individuates it.
b) The souls of living things are substantial forms of their bodies: anima forma corporis. Peter and Paul are living things; hence their souls are individual substantial forms of their bodies. To put it more precisely, Peter and Paul are form-matter composites. The psychic or soulic component in each is the individual substantial form, and the material component in each is the parcel of designated matter. Each component needs the other to be what it is: the psychic-formal component needs the material component for its individuation, and the material component needs the psychic component for its animation. And neither component can exist without the other: each exists only together with the other. Thus the whole of which they are proper parts is not a whole compounded of parts that can exist on their own, as substances in their own right, but a whole the parts of which are mere ‘principles’ in scholastic jargon and thus not substances in their own right. This implies that the hylomorphic whole, which is a substance in its own right, is ontologically prior to the morphic and hyletic parts which are not substances in their own right. Bear in mind that a primary substance, by definition, is a basic entity that is metaphysically capable of independent existence.
c) The souls of humans, unlike those of non-human animals, are subsistent: they are metaphysically capable of independent existence. So the souls of Peter and Paul will continue to exist after their bodily death in a disembodied intermediate state prior to their re-embodiment in the general resurrection.
The triad is inconsistent because (a) and (b) taken together entail the negation of (c). Indeed any two of the propositions, taken together, entails the negation of the remaining one.
In a nutshell: it cannot be the case that souls depend on material bodies for their existence and individuation but continue to exist as individual souls after bodily death in a bodiless state.
What Thomists want to say is that SOMEHOW a substantial form that achieves individuation ‘here below’ pre-mortem by marriage with a hunk of matter, thereby animating said hunk of matter, continues to exist as a disembodied individual soul ‘up yonder’ post-mortem AFTER the individuating factor has been removed. That makes no sense. What would make sense is that the individual soul cease to exist after the death of the body. Bear in mind that the soul on an Aristotelian hylomorphic mereological analysis is a mere ‘principle’ of the hylomorphic composite entity and not itself a substance.
The conclusion to be drawn from this is that despite the Angelic Doctor’s noble attempt to stay as close as possible to The Philosopher (philosophus), he is in the end a substance dualist of sorts, though not quite along Platonic, Augustinian, or Cartesian lines.
There was a time when I thought that, with respect to the soul, Thomas was an Aristotelian ‘on earth,’ but a Platonist ‘in heaven.’ (I may have picked up that line from Anthony Kenny.) But then the problem of the SOMEHOW, the problem of how a human soul can go from a mere non-subsistent ‘principle’ to a subsistent upon the removal of the soul’s individuating factor, becomes insoluble. I now think that it would be better to say that, with respect to the soul, the doctor angelicus was a Platonist in both the sublunary and superlunary spheres, both ‘on earth’ and ‘in heaven,’ and this in consequence of his Christian theological commitments which exercise ‘veto power’ over his philosophical assertions.
A question: Aristotle said that rational thought is not a material operation, and is not associated with any bodily organ. How is that possible on your account of hylomorphism? The thoughts I have are mine alone, part of what individuates me; and your thoughts are yours alone. If individuation follows matter and vanishes with it, how can my thoughts be immaterial?
It would seem that a hylomorphist would have to accept Averroes’ theory that the agent intellect is shared by all humans. But then the fact that I am aware only of my own thoughts, and not yours or Socrates’, becomes mysterious.
Are there some texts in *De Anima* that I ought to review?
>>If individuation follows matter and vanishes with it, how can my thoughts be immaterial?<< An immaterial thought could have a material substratum without which it cannot exist. One can be a dualist without being a substance dualist: epiphenomenalism, emergentism, supervenientism . . . are types of nonreductive physicalism. Aristotle may be a nonreductive physicalist/materalist. This from SEP: https://plato.stanford.edu/entries/aristotle-psychology/#HyloSoulBodyRelaMateDualSuiGene >>In the same way, then, the presence of the soul explains why this matter is the matter of a human being, as opposed to some other kind of thing. Now, this way of looking at soul-body relations as a special case of form-matter relations treats reference to the soul as an integral part of any complete explanation of a living being, of any kind. To this degree, Aristotle thinks that Plato and other dualists are right to stress the importance of the soul in explanations of living beings. At the same time, he sees their commitment to the separability of the soul from the body as unjustified merely by appeal to formal causation: he will allow that the soul is distinct from the body, and is indeed the actuality of the body, but he sees that these concessions by themselves provide no grounds for supposing that the soul can exist without the body. His hylomorphism, then, embraces neither reductive materialism nor Platonic dualism. Instead, it seeks to steer a middle course between these alternatives by pointing out, implicitly, and rightly, that these are not exhaustive options.<<
“Are there some texts in *De Anima* that I ought to review?”
“From this it indubitably follows that the soul is inseparable from its body, or at any rate that certain parts of it are (if it has parts) for the actuality of some of them is nothing but the actualities of their bodily parts. _Yet some may be separable because they are not the actualities of any body at all._” De Anima, book 2, part 1
Aquinas goes beyond Aristotle when he says the human soul *is* separable due to its rational faculties – but he doesn’t contradict Aristotle on that point, because Aristotle allows that separability is *possible* for that reason. And the fact that Aristotle, the inventor of hylomorphism, thought that possible is a problem for your argument that hylomorphism rules out separability.
Michael,
In his SEP article “Supplement to Aristotle’s Psychology: The Active Mind of De Anima iii 5 ” in the SEP, Christopher Shields speaks of the extreme exegetical difficulties that commentators have encountered with regard to De Anima iii 5 and, by logical extension, to De Anima ii 1 , which you cite, and Metaphysics xii 3, 1070a24–6 . Some scholarly commentators favor your belief that Aristotle in these works is referring to the human soul but others hold that he is referring to the divine mind.
On these daunting problems of interpretation, see https://plato.stanford.edu/archives/fall2025/entries/aristotle-psychology/active-mind.html
Vito
A good, clear article on a topic that has exercised my mind for a while. You underline the inability of the Aristotelian-Thomistic tradition to give a good account of anthropology. I would like to know whether you think that Duns Scotus made a better job of it than Aquinas?
Which text of Duns Scotus bears upon the points I make above? Does he somewhere discuss the problem I am addressing?
Bill,
With the help of Grok, I found a few quotations of Duns Scotus on this problem. Writing some thirty years after Aquinas’ death, he appears to have grasped the difficulties of his distinguished predecessor’s argument, along with the limits of the philosophy in the matter of the survival of the post mortem soul.
Ordinatio IV, d. 43, q. 2, n. 4: “The rational soul is the form of the body, and united to the body in the mode of a substantial form; however, separated from the body, it does not remain in complete being naturally, but through a divine miracle, because a form does not subsist without matter except through supernatural power.”
Quaestiones quodlibetales. 9, a. 1, n. 5: “To the first main argument, when it is said that the intellective soul is immaterial, therefore immortal: I say that immateriality does not sufficiently prove immortality, because although it is immaterial with respect to operation, yet it is the form of matter, and consequently depends on matter in its being, just as any other form.”
Quaestiones quodlibetales 9, a. 2, n. 14): “The intellective soul does not have immortality from its own nature, but from the divine will; for philosophers could not prove the immortality of the soul through natural reasons, but it is known only through revelation.”
Vito
Thanks so much Vito, and a tip of the hat to Mr Grok as well. Those Scotus quotations support my position.
I spent some time in a Franciscan friary, and we hosted a visiting Franciscan from Italy for a while. At one point, he became quite agitated in his defense of Scotus over Aquinas concerning the principle of individuation. It was a wonderful conversation – he was in full Italian volume-and-gesticulation mode.
But that is as may be: David Oderberg provides a good explanation and defense of the Thomistic position:
https://drive.google.com/file/d/0B7SKlRTfkUieRWJGMzRadUVaXzg/view?resourcekey=0-CkSL9IYyMy7OqmtFf3gz5w
Precis:
(1) All substances, in other words all self-subsisting entities that are the bearers of properties and attributes but are not themselves properties or attributes
of anything, are compounds of matter (hyle ̄) and form (morphe ̄).
(2) The form is substantial since it actualizes matter and gives the substance its
very essence and identity.
(3) The human person, being a substance, is also a compound of matter and substantial form.
(4) Since a person is defined as an individual substance of a rational nature, the substantial form of the person is the rational nature of the person.
(5) The exercise of rationality, however, is an essentially immaterial operation.
(6) Hence, human nature itself is essentially immaterial.
(7) But since it is immaterial, it does not depend for its existence on being united to matter.
(8) So a person is capable of existing, by means of his rational nature, which is
traditionally called the soul, independently of the existence of his body.
(9) Hence, human beings are immortal; but their identity and individuality does require that they be united to a body at some time in their existence.
This is more or less what Feser says in his recent reply to our gracious host, here, over at his site.