Summa I q.75 a.2: Is the Human Soul Subsisting? Why the Intellect Is Not a Body

Orientation #

He opens: “we’re looking at Article Two and maybe Article Three today.” The tail of the previous discussion is audible before the prayer: it is through health that I am healthy, “but it’s not through any of these that I am.” He refers back to the senses in the De Anima (“if you’ve seen this already in the senses”) and to “the order of reasoning, which is what we said” (prev. lecture). The previous class treated q. 75 a. 1 (the soul is not a body); the next treats the replies to the three objections of a. 2.

The class, in order #

1. The question and its word (“What does that word subsisting mean”) #

Article 2 asks whether the human soul is something subsisting. Subsisting: “having existence in its own right,” existence by itself.

2. The three objections (“perhaps the most interesting one”) #

• Obj. 1: what subsists is a hoc aliquid, a this-something (his gloss: translation of Aristotle’s tode ti, said of individual substances); the soul is not a hoc aliquid, but the composite of soul and body is; therefore the soul does not subsist.
• Obj. 2: whatever subsists can be said to do something; but Aristotle in De Anima I says that to say the soul senses or understands is like saying it weaves or builds; therefore not subsisting.
• Obj. 3: if the soul subsisted, it would have some operation without the body; but it has none, not even understanding, since it does not understand without a phantasm or image, and the image is not without the body. He ranks them: the first two rest on how you take hoc aliquid (Thomas distinguishes two senses in the reply) and on Aristotle “not necessarily speaking according to his own opinion.” The third is “the most substantial,” the one people bring up in some form: a blow to the brain interferes with thinking, so most people think the brain is the organ of thought as the eye is of seeing. Thomas will solve it “in the way that you see me solve it” (not given here).

3. Sed contra: Augustine on the mind (“the images of what bodies”) #

Augustine, De Trinitate X. Mens in Latin is often not just reason but the soul insofar as it is above matter, a spirit with a reason and a will that are not bodies. Whoever sees the nature of the mind sees it is a substance and not a body; those who think it bodily err because they join to it what they cannot think any nature without, namely images of bodies. His comment: we never think without imagining, and never imagine anything but something body-like and continuous, so if we judge everything by our images we think everything bodily. Hence the mind is not only incorporeal but a substance, something subsisting. Aside: “substance” etymologically stands under the accidents; “subsisting” is said rather because it has existence by itself.

4. Body of the article: reason knows all bodies, so is not a body (“cannot perceive something what sweet”) #

Thomas: the source of the operation of understanding, which we call the soul of man, is an incorporeal and subsisting principle. Shown by Aristotle’s main argument in De Anima III:

1. Man through understanding can know the natures of all bodies. Sign: we know body in general, what it is to be a body; we distinguish living from non-living; we go from the confused to the distinct down to bodies in particular.
2. What can know some things must have nothing of them in its nature, because what exists in it naturally would impede knowledge of the others. Thomas’s example: the tongue of a sick man infected with a bitter humour cannot perceive sweet, all seems bitter; Berquist’s reversal: a sugary tongue could not taste bitter.
3. Every body has a determined nature; so if the intellectual principle had the nature of some body, it could not know all bodies. Therefore it is not a body. Background he supplies from the De Anima: Aristotle begins with the senses, which know by receiving qualities (eye colours, ear sounds) and so must lack what they receive. Green lenses in the eye, as in the Wizard of Oz: everything appears green. Mozart “built into my ear”: I would hear it but nothing else. The senses can be bodies because they do not know everything: the eye knows only colour; a red tongue is no impediment to tasting since the tongue does not know colour. “This is the first argument Aristotle gives, and Thomas appropriately gives that to beginners”; it is far more accessible once seen in the senses. Corollary read: nor can it understand through a bodily organ, since the organ’s determined nature would likewise prohibit knowledge of all bodies; Thomas’s example, a colour not only in the eye but in a vase or glass dish: liquid poured in seems that colour.

5. From operation to existence: “reasoning backwards” (“you must be before you can do something”) #

He flags what Thomas is doing: reasoning from the operation of the soul (not in the body) to its existence (not tied to the body), “the order of reasoning” spoken of before. A student asks why the article, which asks about subsisting, goes back to incorporeality. His answer:

• Descartes’s cogito, “I think, therefore I am”; equally “I talk, therefore I am,” “I walk, therefore I am.” You must be before you can do or undergo anything, whether material or immaterial.
• Aristotle, ninth book of “wisdom” [ed.: Metaphysics IX]: motion seems most real to us though least real of all acts. What does not exist can be thought, imagined, wanted, but no one thinks it moves. So the mind sees that being is before doing.
• Sherlock Holmes to Watson: “we’re going to have to reason backwards,” from effect to cause. As far as reality goes our thinking is backwards; God, first in reality, is the last thing the philosopher reasons to. Applied: if the soul’s existence were only in the body, “immersed” in it, it would do nothing except in and through the body. But it understands (or chooses) not in the body; therefore its existence is not only in the body, it has existence by itself.

6. Plato’s Theaetetus and the road to Aristotle (“Aristotle completes that work that Plato began”) #

In the Theaetetus Socrates notes that we sense colour, sound, flavour, and also say colour is different from flavour; not by the eye nor by taste, so the soul says it “by itself,” not through a bodily organ. Plato thus goes straight from the outward senses to something inward not in an organ. Aristotle instead interposes the common (central) sense: that colour and flavour are not the same what is proper to reason, but we also sense the difference between red and sweet, which seems to require something bodily; then he distinguishes common sense, images and reason. Plato is “on the way.” Asides: the dialogues raise questions not fully answered; we have no lectures from the Academy, and the dialogues may have been written for those coming into it (“Let no one ignorant of geometry come in here”); whether Plato got further in the Academy than in the dialogues we cannot know. Aristotle spent 20 years there (17 to 37), left at Plato’s death; Speusippus, the nephew, took over since the head had to be an Athenian; Aristotle later founded the Lyceum. Hence “Lyceum” in Lincoln’s speeches and the Lyceum Theater in St. Paul; “Academy” and “academic” likewise. “You should know something about Plato.”

7. The article’s conclusion: per se operation, per se existence (“in that way something operates in which it is”) #

Thomas: the intellectual principle, called mind or understanding, has an operation per se, to which the body does not communicate; but nothing operates by itself that does not subsist by itself, for to operate belongs only to a being in act; hence in the way a thing is, it operates. A student stumbles on the Latin word order (eo modo … quo est); he re-translates: eo modo refers to operatur; “in the way a thing is, so does it act.” If it existed only in the body it would operate only in the body; it operates in understanding not in the body; so its existence is not only in the body. Student: is this agere sequitur esse? “Yes, in slightly different words.” Aside: his joke on modern confusion, student asks “Do I exist?”, professor: “Who’s asking?” Merely asking, you must exist.

8. Further route: thought is not continuous but like number (“thoughts are like what numbers”) #

A whole series of arguments follows if you see the connection between body and the continuous, and the non-continuous character of thought.

• First definition (Categories): the continuous is that whose parts meet at a common boundary. Left and right halves of a line meet at a point; halves of a circle or the diagonal of a rectangle meet at a line. Contrast discrete quantity: 3 and 4, 2 and 5 in seven meet nowhere. Geometry vs. arithmetic.
• Second definition: divisible forever. A line cut yields shorter lines; it could stop only in two nothings (nothing is made of nothing) or two points, and two points can only touch by coinciding, since a point has no parts, no edge distinct from itself, only position; a million or an infinity of coinciding points have no more length than one. Number is not divisible forever: 7, 3+4, 2+2, and one is indivisible; the one is even simpler than a point (“a point is a unit having position”). So De Anima I: thoughts are like numbers.
• Why thoughts are not divisible forever: (a) reasoning: if every statement needed proof, infinitely many unproven statements would precede any, and nothing could be known; but we know some (“statements exist”; the denier makes a statement); (b) definition: blank verse is unrhymed iambic pentameter, an iamb is two syllables accented on the second, accent is…, if this went on forever definition would be impossible and one could not even know what “definition” means; (c) words: the dictionary explains words by words, but we come into the world knowing none, so the first words are learned through the senses (“Want a cookie?”, a tape of his firstborn).
• Common boundary: in “triangle is a three-sided plane figure,” three-sided and plane figure meet at no point (else the definition would be a line), no line, no plane. So I know a continuous thing in an uncontinuous way; since that is not due to the thing known, reason is not continuous, hence not a body. Likewise “what a straight line is” has no length, else it would not be common to all straight lines.
• Next: in “every mother is a woman, no man is a woman” the next statement is “no man is a mother” (second figure, the form used constantly in theology: what changes is composed, God is not composed, God does not change); after three the next number is four; but there is no next longer straight line, since any added length is divisible forever. “Next” means nothing between, as with the next-door neighbour or the next chair. From quadrilateral to square there are two thoughts (equilateral, right-angled), not an infinity of intermediaries; between two lines of different length, infinite points. “The more you study what the continuous is… the more you see thought is not something continuous, and therefore not bodily, because the body is always continuous.”

9. Further route: reason receives the universal apart from what individuates (“what a circle is neither here nor there”) #

The object of reason is the what-it-is of something sensed or imagined, which is universal (what a dog, a cat, a chair is). Boethius: the thing is singular when sensed or imagined, universal when understood. In material things many individuals of one kind are possible: two identical circles on the board differ only by position, and position belongs to the continuous, part outside part; a plate of glass yields many panes, enough wood many chairs. So the source of many individuals is enough matter. What a circle is is neither here nor there; if it were received in something continuous it would be received here or there, i.e. as singular. Reason receives it universally, without the conditions of the continuous, knowing the singular only by returning to imagination and sense; therefore reason is not continuous, not a body. Locke’s “very hard” general idea of triangle (neither scalene nor isosceles nor equilateral, neither right nor obtuse) is the error of trying to imagine the universal; one can only imagine an individual triangle of some kind, but geometry demonstrates of the triangle as triangle (interior angles equal two right angles, via the parallel through a vertex and alternate angles). Plato’s Parmenides: young Socrates imagines the universal as a sail over everyone, so each would have only part of “man”, one the animal, another the rational. Closing line: they also point to the understanding knowing what truth is, things that do not seem to be a body at all, yet are in it; how then could it be a body?

His words #

• subsisting: having existence in its own right, by itself.
• hoc aliquid: a this-something; his gloss, Aristotle’s tode ti for individual substances.
• mens: often the soul insofar as above matter, spirit, not only reason.
• substance: etymologically what stands under the accidents.
• “ninth book of wisdom” [ed.: Metaphysics IX].
• reasoning backwards: from effect to cause, from doing to being (Sherlock Holmes).
• eo modo… quo est: “in the way a thing is, so does it act”; student’s agere sequitur esse accepted.
• common sense / central sense: Aristotle’s inward sense of the difference between red and sweet.
• continuous: (1) that whose parts meet at a common boundary; (2) divisible forever.
• discrete quantity: number; parts meet nowhere; not divisible forever.
• point: no parts, no length/width/depth, has position; “a unit having position.”
• next: nothing in between (next-door neighbour, next chair).
• universal: neither here nor there in the continuous; the continuous is what individuates.

Texts #

Read in class

• Thomas Aquinas, Summa Theologiae I, q. 75, a. 2: objections 1-3, sed contra, body (verified).
• Augustine, De Trinitate X (as quoted in the sed contra).
• handout, On the Natural Fragments, p. 33 (verified; probably the passage on the continuous, not explicitly named in the transcript). Mentioned
• Aristotle, De Anima III (argument from knowing all bodies; senses lacking what they receive); De Anima I (soul weaving/building; thoughts like numbers, “a part we didn’t read”).
• Aristotle, Metaphysics IX (motion seems most real).
• Aristotle, Categories (definition of the continuous).
• Plato, Theaetetus; Plato, Parmenides.
• Boethius (singular when sensed, universal when understood; no locus).
• Descartes, cogito; Locke on the general idea of triangle; Sherlock Holmes; Wizard of Oz; Shakespeare’s blank verse.

His questions #

• What does “subsisting” mean? Having existence in its own right, by itself.
• Which objection is the most substantial? The third: no operation without the body, since understanding needs an image; the “brain is the organ of thought” objection.
• Why does Thomas, asked about subsisting, go back to incorporeality? Because one reasons backwards, from operation to existence: a thing must be before it does; if it operates not in the body, its existence is not tied to the body.
• Do we say by the eye, or by taste, that colour is not sweet? Neither; Plato: the soul by itself; Aristotle: the common sense senses the difference, reason knows the difference of natures.
• Can a straight line be cut into two nothings, or composed of points? No; nothing comes of nothing, and points can only touch by coinciding.
• Does every statement have a statement before it, every definition a definition, every word another word? No, or nothing could be proved, defined or named; first words come through the senses.
• Do three-sided and plane figure meet at a point, line or plane? No; the definition is not continuous, so reason knows a continuous thing uncontinuously.
• Is there a next longer straight line, as four is the next number after three? No; any added length is divisible forever, whereas thoughts have a next.
• How do two identical circles differ? Only by position, which belongs to the continuous; what a circle is is neither here nor there.
• Can you imagine triangle in general? No, only an individual of some kind; but you can understand it (Locke’s and young Socrates’ error).