De Anima II.2: Definition and Demonstration, Wonder, and Reasoning from the Soul's Activities

Orientation #

He opens by recalling what was done “in the first chapter”: the definition of the soul reached by six divisions and manifested by two proportions (prev. lecture). He also recalls the beginning of the “natural hearing” (Physics I), the study of the four kinds of causes, and Plato’s and Aristotle’s texts on wonder “that we mentioned before.” The previous class worked through De Anima II.1 to the definition of the soul as first act of an organic body; the next examines the powers of life (nutrition, sensation, understanding) and their hierarchy.

The class, in order #

1. What Aristotle does in the second chapter (“one must try once more to recount the soul”) #

The point: chapter 2 does not add to the definition but, “in a way, syllogizes”: it demonstrates the definition of the soul through a middle term more known to us.

• The definition was reached by division on two sides: the side of the soul itself, and the side of that of which the soul is an act.
• He dislikes the translation of the opening sentence somewhat; his gloss: from things unclear but more manifest (to us) comes what is clear and more known kata ton logon, “according to reason.” This touches what Physics I said about more known to us vs. more known by nature, “but it’s not said as clearly.”
• The Greek peirateon (“one must try”) shows the difficulty.
• So the direction is: from second act to first act, from more known to us to more fundamental in reality.

2. The squaring example: two accounts of one thing (“the finding of a mean proportional”) #

The point: a definition may be like a conclusion, or may state the cause; Aristotle’s example is squaring.

• Squaring as “making an equilateral [figure] equal to an oblong” has the account of a conclusion; squaring as “finding the mean proportional” says the cause.
• Worked with a student in numbers: 4 and 9 are the sides of an oblong (4×9 = 36); the mean proportional is 6 (4:6 :: 6:9), and 6×6 = 36. A mean proportional is a number to which one extreme is as it is to the other.
• In geometry it is done with lines rather than numbers (he refers to a construction at the end of a book of Euclid, “with two” [ed.: Elements II, inferred]); the task is to turn any rectangle that is not a square into a square of equal area.
• Mapping: the mean proportional is like the middle term; the square equal to the oblong is like the conclusion. Find a square whose side is the mean proportional between the oblong’s sides and you have a square equal to the oblong.

3. Digression: logic, wonder, and the questions what and why (“no other beginning of philosophy than wonder”) #

The point: the comparison of definition and demonstration in Posterior Analytics II matters because logic is the tool of the man who wonders, and wonder asks both what and why.

• Logic is the tool of the man who thinks, i.e., the philosopher (not of practical thinking as such).
• Plato, Theaetetus: Theodorus introduces Theaetetus as “something of a philosopher”; when Theaetetus breaks out in wonder, Socrates says Theodorus guessed rightly, “for there is no other beginning of philosophy than wonder.” Aristotle, proemium to wisdom (beginning of the Metaphysics): wisdom is knowledge sought for the sake of understanding, not for doing or making; his sign is that men began and begin to philosophize out of wonder. The “two chief philosophers,” as Thomas calls them, agree.
• Consequence: what is done not out of wonder is philosophy only equivocally.
• Harmony with the word “philosopher,” lover of wisdom: one must love wisdom for its own sake, not for money or admiration. Comparison: a man who loves a woman for her money loves the money, not the woman; if she asks and he answers honestly, she says tearfully “then you don’t love me,” and we all agree. Film illustration, The Heiress (Olivia de Havilland; wealthy Dutch patroon on the Hudson): the father offers the suitor money to go away, and his taking it is the sure sign he loved the money. Loving her “for her money” is love only secundum quid. Likewise loving wisdom for anything else is being a lover of that other thing. Wonder is a desire to know simply for the sake of understanding, so the word and the beginning harmonize.
• Aristotle and Thomas usually define this wonder as a desire to know the unknown cause of a known effect.
• Democritus’s fragment, “I would rather discover one cause than be master of the kingdom of the Persians”: Persia was the greatest kingdom the Greeks knew; its master would have excess of everything men want (wealth, power, honor to the point of being worshipped as a god, sense pleasure; the thousand chefs who would lose their heads over a bad meal). So the fragment expresses intense desire to know causes, ultimately first causes. The early philosophers (Thales: water the beginning of all things) all sought the causes of natural things, apparently the first causes of all.
• But Plato’s text has Theaetetus wonder “what these things are,” and Socrates afterwards asks whether he now understands “why these things are so.” Hence wonder can be defined as a desire to know what and why (“Twinkle twinkle little star, how I wonder what you are”).
• Posterior Analytics II treats exactly these two questions: definition is the speech answering what; demonstration is the syllogism answering why. Why asks for the cause; answering what also gives the causes responsible for the thing being what it is. Hence Aristotle’s comparison of definition and demonstration, “a very important comparison.”

4. Definition as beginning, conclusion, or whole of a demonstration (“a tool for cutting”) #

The point: Aristotle’s summary, that a definition can be the beginning of a demonstration, its conclusion, or the whole demonstration in a different form, requires seeing that there are several kinds of cause.

• Knife: (a) “a tool for cutting” defines by the end; (b) “a tool having a blade inserted in a handle” defines by parts, and since parts are like matter, by matter; (c) the grand definition combines them (“a tool for cutting, composed of a blade and handle,” or with the order reversed).
• Syllogism from one to the other: a knife is a tool for cutting; a tool for cutting needs a blade to cut with and something we can hold without being cut; therefore a knife is a tool composed of blade and handle. Here definition (b) is like the conclusion, definition (a) like the middle term and beginning; definition (c) contains everything in the demonstration “but in the form of a definition.” He notes the demonstration must be a syllogism with rigor in its premises.
• Marriage: his complete definition, “a stable union of a man and woman by mutual choice for the sake of children,” is a definition in the third sense (student answers “third”): it differs from a demonstration “in form and position” but contains what it would contain. Reasoning form: marriage is a society for generating and educating children to mature citizens and members of the church (middle term); such a society cannot be of two men or two women, must be of a man and woman, and must be stable to raise them; therefore marriage is a stable union of a man and woman (conclusion). “Stable union” is on the side of form, “by mutual choice” the efficient cause; the matter is what most clearly stands as a conclusion from the end.
• Aristotle himself illustrates this in Posterior Analytics I: he defines demonstration from its end or purpose, then reasons to what the premises must be.
• Definition of definition: “speech making known distinctly what a thing is” (middle, beginning) and “speech composed of the genus and differences of a thing” (conclusion): if speech is to make known distinctly what a thing is it must say in general what it is (genus) and bring out its differences from what shares that. Grand definition: “speech composed of the genus and differences of a thing, making known distinctly what that thing is,” everything the demonstration has, “in the position of the grand definition rather than the position of demonstration.” Aristotle does the demonstration in Book I and speaks of it in general in Book II.

5. The middle term for the soul (“that by which we first live, sense, move, and understand”) #

The point: Aristotle will demonstrate the definition reached by division, that the soul is the first act (substantial form, “as one says”) of a natural body composed of tools, through a middle term more known to us and “a little bit like the end”: the operations of life, the second acts.

• The two premises he must develop: (1) the soul is that by which we first live, sense, move, and understand; (2) that by which we first live, sense, move, and understand is the form of the body, not the matter. “Living” here is in the sense we share with plants.
• So it is like having two definitions of the soul: “first act of a natural body composed of tools” and “that by which we first live, sense, move, and understand.”
• Parallel, reasoning to a virtue through its act: temperance is that by which I eat and drink moderately; but that is not the appetite for food (we are all born with it, so it is the subject, not the answer), but a disposition or habit of the appetite, i.e., a form the appetite has received.
• Plato’s proportion: emotions are to reason as a horse to a man; the horse first resists and tries to throw the rider, and if you give up the horse leads you, but if you get back on it calms and obeys; so appetite must be trained and habituated to obey. Tamed horse vs. horse in the field: same things by nature, one has acquired a custom or habit. Likewise training a dog, or even a cat to use its box.
• Aside: Washington Irving’s A Tour on the Prairies, written after his return from Europe because the public expected something on the West; describes how quickly captured wild horses were tamed; “a master of English prose.”

6. Why the operation points to the form (“Once it has its form, its arrangement”) #

The point: the general sign for premise (2): tools are first able to do their work not when the materials are merely present, but when they have been shaped, formed and ordered.

• Example: fans bought for the house come out of the box unassembled; only once assembled, once they have their form, do they do what they are supposed to do.

His words #

• “natural hearing”: his name for Aristotle’s Physics [ed.: Physics].
• “more known to us” vs. “more known according to account / by nature” (kata ton logon): the direction of the chapter’s reasoning.
• peirateon (Greek): “one must try”; he notes it signals difficulty.
• “syllogize / demonstrate the definition”: what chapter 2 does with the definition reached by division.
• “mean proportional”: a term to which one extreme is as it is to the other; like a middle term.
• “the proemium to wisdom”: the beginning of the Metaphysics.
• “the two chief philosophers”: Plato and Aristotle, as Thomas calls them.
• “wonder”: desire to know the unknown cause of a known effect; also desire to know what and why.
• secundum quid: loving a woman “for her money” is love only in a qualified sense.
• “definition”: speech making known distinctly what a thing is; also speech composed of genus and differences.
• “demonstration”: the syllogism answering the question why.
• “grand definition”: his name for a definition containing what a demonstration contains, differing “in form and position.”
• “first act” / “second act”: the soul vs. the operations of life.
• “composed of tools”: his rendering in the definition of the soul [ed.: organic].
• “that by which we first live, sense, move, and understand”: the middle term / second definition of the soul.
• “ability”: what we are born with, e.g. the appetite [ed.: potency]; contrasted with habit or disposition.

Texts #

Read in class

• Aristotle, De Anima II.2, opening sentences (“from what is unclear, but more apparent…”; the definitive account must show the cause; the squaring example).

Mentioned

• Aristotle, Physics I, on what is more known to us vs. by nature.
• Aristotle, Posterior Analytics II (the questions what and why; definition and demonstration) and Book I (definition of demonstration from its end).
• Aristotle, Metaphysics I, proemium (wisdom as speculative; men philosophize out of wonder).
• Plato, Theaetetus (Theodorus, Theaetetus, Socrates on wonder); Plato’s horse-and-man comparison (no locus given).
• Democritus, fragment on the kingdom of the Persians.
• Thales, water as the beginning of all things.
• Euclid, Elements, end of a book, construction of a square equal to a rectangle (inferred: II.14).
• Thomas on the “two chief philosophers” (no locus given).
• Washington Irving, A Tour on the Prairies; the film The Heiress; “Twinkle twinkle little star.”

His questions #

• What is Aristotle going to do now in the second chapter? In a way syllogize: demonstrate the definition of the soul through a middle term more known to us.
• Can you expound the mean proportional to me? With 4 and 9 (an oblong, area 36) the mean proportional is 6, and 6×6 = 36; the square on it equals the oblong.
• Which is like a middle term, and which is like a conclusion? The mean proportional is like the middle term; the square equal to the oblong is like the conclusion.
• What was the beginning of philosophy, according to Plato and Aristotle? Wonder; there is “no other beginning.”
• If a man loves a woman for her money, does he love the woman or the money? The money; likewise one who loves wisdom for anything else is not a lover of wisdom.
• My definition of marriage is a definition in which of the three senses? The third: the whole demonstration in a different form and position.
• Is temperance the ability we are all born with to feel hunger and thirst? No, we all have that; it is the habit or disposition, the form the appetite has received.
• When are tools first able to do their operation? Not when the materials are merely there, but when they have been shaped, formed and ordered, i.e., have their form.