Modern Physics, Knowing by Making, and the Closed Circle of Man

Orientation #

He opens by stopping the reading: “we’ll start here with reading eleven next time,” two weeks off because of tile work at his house. Verified sources place this episode probably between Aquinas’s lectio 10 and lectio 11 on Physics I (inferred), with a five-minute read from the handout “The First Statement and King of Statements” (p. 3) and DHB Vol I p. 103; the page numbers he himself calls out for the physicists’ quotations are 4, 5 and 6. The neighbouring classes work through Aristotle’s argument that two contraries need a third, underlying principle.

The class, in order #

1. Housekeeping, the cat, and “more or less than the truth” (“reading eleven next time”) #

Reading eleven is deferred two weeks; the informal talk that follows is the substance of the recording.

• The death of a student’s cat (“a little philosopher cat”) leads him to the Summa Contra Gentiles, where Thomas discusses and refutes Plato’s opinion that the souls of cats and the other animals are immortal. The moderns hold all souls mortal, Plato that all animal souls are immortal; “the truth is in the middle” between the two extremes.
• Thomas’s phrase “more or less than the truth” (the liar says either more or less than the truth) he pairs with a line he attributes to Faustus [ed.: he asks “do you see that phrase in Shakespeare?”]: those who say more or less than the truth “are knaves and the sons of darkness.”

2. Student: Einstein’s “matter is condensed energy” (“energy is in fact the substance”) #

A student is confused by last week’s quotations (Einstein: matter is condensed energy; Heisenberg: energy is the substance of the elementary particles). His answer: “substance” there means matter.

1. Aristotle in the Metaphysics calls matter substance, form substance, and the composite substance; the moderns keep only the sense “matter.”
2. Student: isn’t energy then an accident? Reply: for the physicist energy enables you to do things, so it looks like a mover; but mass can be generated from energy, so energy is treated as the source of matter, matter being understood as mass.
3. “You have to be careful because all this is a mathematical science. You don’t really have any matter there.” Schrödinger, who perfected the mathematics of wave mechanics and showed its equivalence to quantum mechanics, says the modern atom “consists of no stuff at all,” comparing it to the geometrical earth, air, fire and water of Plato’s Timaeus. Hence the communists grew nervous: matter seemed to be disappearing from physics, and Marxism makes matter the beginning of all things.
4. Mathematics contains neither matter nor motion; so one is “studying matter in motion with mathematics that contains neither matter nor motion” — a very strange kind of knowing. Physicists sometimes sense this: “shadowing, but not containing.”

• Student: is matter really the same as energy? Reply: originally there was a conservation of mass and a conservation of energy; then it was found that mass is not conserved — accelerated particles colliding can yield particles with more mass than the originals — so mass becomes subordinate to energy, and E = mc² makes them equivalent.
• Words like mass and force resemble matter and mover but are defined by ways of measuring; they are technical language, and the transition to ordinary or philosophical words must be made carefully. Aside: he once asked Kusnig whether the physicist’s force is what we mean by mover, “and he just laughed in my face.”

3. Going back to the Greeks; grammar as a case (“we reverence ancient Greece”) #

A student reports spending a study period re-reading all his natural-philosophy notes to see if he could teach them; he approves, and turns it into a point about the Greeks.

• Heisenberg’s nuclear physics lectures begin with the early Greeks: whoever wants to understand nuclear physics should go back to them. Einstein: “we reverence ancient Greece as the cradle of Western science” — “cradle” sounds diminutive, “reverence” is strong. Schrödinger: science is the Greek way of looking at things; no one has had science who has not touched the Greeks — not a definition of science, but a compliment.
• Almost everything is Greek: they fathered both geometry (rigorous) and tragedy (imaginative); the Romans imitated (Comedy of Errors imitates Plautus imitating Menander).
• Grammar example, from someone learned in grammar: the Romans could not reflect on their own language, so they imposed Greek grammar on Latin. Greek has four cases ordered perfectly — genitive (imagined before the action of the verb), dative (with it), accusative (after it); Latin took these over and tacked the ablative on fifth. But Latin uses the ablative where Greek uses the genitive (Thomas points this out commenting on Greek texts in Latin), so the order is fouled up; and the Latin dative belongs after the accusative (“I gave the book to you” — the book is closer to the giving than you are). English grammar is more fouled up still, imitating Roman grammar. Latin lacks the article; medieval writers, Thomas sometimes and Cajetan more, invent one.
• Homer is far superior to Virgil; in philosophy the Romans do not compare; Romans are good at law, “more practical than the Greeks.”

4. Black-body radiation and Bohr’s atom: contradiction in classical physics (“never went through the middle”) #

Asked to explain the black-body experiment and why it failed Newtonian expectations, he says he cannot; it led to impossible consequences such as infinite energies. He offers instead the Bohr atom as a case where classical physics runs into contradiction:

1. If an electron drops from a higher to a lower orbit it loses energy, which must be emitted.
2. If that drop is a change of place, the change is continuous, so the emission should be continuous.
3. But the observed emission is jump-like: “it’s here and then it’s here, but never went through the middle.” Conclusion: they began to doubt that this is change of place at all, and so to break down the idea that the only change in the world is change of place.

• Heisenberg’s remark that we know matter only through its forms is “very close to Aristotle”: first matter is only ability, known through its forms, not by itself. But such comparisons need care, since modern science is a strange knowledge.

5. Bohr: “extend the range of our experience and reduce it to order” (“what are you reducing to order”) #

He has long used Bohr’s opening line to mark the two parts of experimental science, the empirical (extend the range of experience) and the theoretical (reduce it to order). Thinking harder about it, the sentence is strange: taken as it stands, it is our experience that is being ordered.

• Contrast: Aristotle in natural philosophy is looking for order in the things we commonly experience, not in our experience of them. Warren Murray, when told, agreed: “isn’t that strange.”
• Parallel with Kant: we do not know the thing in itself, only phenomena; so what is ordered is our experience of the world, not an order in reality.
• He is “still not altogether sure that’s exactly what they’re doing or only what they’re doing” — is Bohr describing what he does, or what he thinks he does? Similar statements appear in other scientists.
• Aristotle, looking at change, finds or recognises an order: something is dry before it becomes wet, sick before healthy — “that’s a before in things.”

6. Weizsäcker read from the handout: knowledge and power (“only that is still comprehensible to us”) #

He reads from Weizsäcker’s The World View of Physics (handout pp. 5–6), remarking that out of context it “sounds just like Karl Marx,” though Weizsäcker is a Lutheran and no Marxist.

• First reading (p. 5): scientific thought proves itself only in the successful experiment; to experiment is to exert power on nature, and the possession of power is the ultimate proof of correctness — “the extension of Bacon, but even more radical.” The limits of concepts show up only as the impracticability of experiments (absolute speed — relativity; position and impulse of an electron — complementarity, Bohr). Older ideals of science are surprised that non-demonstrability is treated as non-existence; since Galileo the criterion of truth is the experiment.
• Second reading (p. 6): pressing to the infinitely small (Heisenberg) or infinitely distant (Einstein), only that remains comprehensible “which is of our making, or which at least could be of our making”; knowledge and power belong together; concepts must be given up for objects that cannot become the object of a subject; pragmatic science fits a technical age. He flags the second paragraph as the strange one.

7. If we know only what we make, the circle closes around man (“the circle has been closed around man”) #

The argument he draws out, with Marx as its explicit form:

1. Man knows only what he makes (Weizsäcker; Marx: the decidedness of thought is a practical question).
2. Man is the beginning and the end of all he makes.
3. So he is the beginning and the end of all he knows — “he is God, to himself.” Corollaries:

• Back to the text of Thomas on the orders of reason (handed out earlier): only in the natural order does reason know an order it did not make; in natural science so understood one knows nothing one has not made.
• Man cannot rest in such a world, because what he makes is inferior to him. Contrast: the world God made is inferior to God, and on the seventh day God rested from all he had made — Thomas: he did not find his happiness in what he made but in himself. Man is not universally perfect, so he cannot rest in himself either; the only way out is “the state of natural things,” which this view denies him. “So he’s going crazy.”
• Marx’s deduction: we cannot even talk about what we have not made, so the result is a “practical, pragmatic atheism.”

8. Kant’s second preface: geometry and experiment as making (“you got to draw that line”) #

Kant says the same — reason knows only what it has made — and takes geometry as the model: the geometers found they could not simply look at figures, they had to do something with them.

• Aristotle’s use of the same fact, distinguished from Kant’s: to see that the three angles of a triangle equal two right angles you must draw a line through the vertex parallel to the opposite side; to see that the angle in a semicircle is right you draw a line making two triangles (four right angles, the four angles at the diameter making two, equal pairs from the equal radii, hence the inscribed angle is half of four, a right angle). For Aristotle this shows the tie between understanding and being in act: the undrawn line is only able to be understood; drawn, it is actually understood. Kant takes it as a sign that one must make in order to know.
• His own class discussion that day: how do you know the diameter bisects the circle? Thales’ way: if the halves do not coincide the radii are not all equal. Students suspect this is as arbitrary as defining the diameter as the bisecting line — but the definition is a line from any point on the circle through the centre to the opposite side, not “the line that bisects.” And the equality of the radii escapes arbitrariness by constructing the circle: rotate a line about one endpoint, and every point of the circumference is equidistant from that endpoint, which is the definition. Hence Euclid begins with the point and builds up: the moving point makes a line (Plato), with length but no width; the rotating line makes a circle; two circles make the equilateral triangle. “So you have to make these things to know them — there’s some truth to that,” and it is partly why geometry is a liberal art and natural philosophy is not.
• Kant then cites three experiments (Galileo’s rolling balls, Torricelli, Stahl): “a whole light dawned upon them” that the natural world is known by making, since the experiment is made by us. Marx deduces the consequence.

9. Student objection; the madness of a self-made world (“solitary confinement of the human race”) #

Student: Kant seemed to be exaggerating; in an experiment you are still trying to see something in nature. He agrees but presses the point that if that is the only knowledge one is used to, the mind is closed within the world of its own making.

• From an old conversation with Warren: the anguish of the modern mind is that it tries to live in a world entirely of its own making, which cannot satisfy it because it is inferior to it. Like solitary confinement, which drives prisoners insane: “modern man is trying to live in solitary confinement,” hence postmodernism.
• Illustrations: an article by Riley on Schoenberg and those who deny anything natural in music; Norman Rockwell now admitted to museums because people like art true to human nature, whereas modern art is “unpopular art” one must be initiated into; a concert piece where the players sit ten or fifteen minutes in silence and leave — “beyond satire” (Marcus).
• Return to Bohr: what we know is the order of our experiences, not an order in things. The same thinking underlies people saying “Saint Thomas created a great system” — he did not; “then you’d be knowing what he made.” His own counter-case: spring, summer, fall, winter is an order in things, not one made by him — he freezes and overheats accordingly.

10. Tinbergen’s wasps and Heisenberg’s own qualifications (“science alters and refashions the object”) #

Student: even in experiment the scientist is not the demiurge; much is not made by him, and the results come from the natures of things — e.g. Tinbergen moving the ring of pine cones so the wasp flies to where the hole is not, showing the wasp sees a pattern: a made situation that nonetheless lets one know nature itself. Reply: “there may be some exaggeration to this, but you do see them saying this.”

• Louis de Broglie: the order known may in some not-understood way reflect an order in things, but it is still not direct knowledge of the order in things.
• Heisenberg (handout p. 4, bottom; p. 5, top), read and commented: objective reality of elementary particles is too crude; the process of observation cannot be ignored; for everyday objects the observing process plays only a subsidiary role (“that’s what philosophy is more closely related to”); with the smallest particles every observation is a large disturbance; science cannot speak of nature in itself and presupposes man; Bohr: we are actors, not merely observers; science alters and refashions its object. “There’s some truth to that.”
• The principle from “the central question of philosophy” in Aristotle: does truth require that the way we know be the way things are? The modern scientist may confuse this, Marx certainly does. If the way we know is by making and the way we know must be the way things are, then we can know only what we make; but an experiment “might help you know something about what’s there apart from your experiment” — so the inference is “not altogether true.” Left there as the recording ends.

His words #

• more or less than the truth — Thomas’s phrase for the liar; matched with “knaves and sons of darkness”
• substance as matter — the one sense of substance the moderns keep, of Aristotle’s three (matter, form, composite)
• “no stuff at all” — Schrödinger on the modern atom
• shadowing, but not containing — the physicists’ own inkling that mathematics does not contain matter or motion
• before the verb / with the verb / after the verb — his gloss of Greek genitive, dative, accusative
• the empirical part and the theoretical part — his reading of Bohr’s “extend … and reduce it to order”
• an order in things vs. an order in our experience of things — the contrast between Aristotle and Bohr/Kant
• ability — first matter known only through its forms [ed.: potency]
• the circle closed around man — man knowing only what he makes
• pragmatic atheism — Marx’s consequence
• liberal art — geometry, because there is a making in it; natural philosophy is not
• the central question of philosophy — whether truth requires that the way we know be the way things are
• solitary confinement of the human race — the modern mind in a world of its own making

Texts #

Read in class

• Weizsäcker, The World View of Physics — two passages, handout pp. 5–6
• Heisenberg, The Physicist’s Conception of Nature (inferred title) — handout p. 4 bottom and p. 5 top
• Niels Bohr — opening line, “to extend the range of our experience and reduce it to order” (quoted from memory)
• Verified sources: handout “The First Statement and King of Statements” p. 3; DHB Vol I – The First Philosophers, p. 103

Mentioned

• Thomas Aquinas, Summa Contra Gentiles — refutation of Plato on immortal animal souls
• Aristotle, Metaphysics — matter, form and composite as substance
• Schrödinger — on the atom and Plato’s Timaeus
• Heisenberg, nuclear physics lectures — first chapter on the early Greeks
• Einstein — “we reverence ancient Greece”; E = mc²
• Kant, Critique of Pure Reason, second preface — geometry; Galileo, Torricelli, Stahl
• Aristotle — drawing the line to make the theorem actually understood (locus not stated)
• Thomas, text on the orders of reason (handed out earlier; locus not stated)
• Thomas on God resting on the seventh day (locus not stated)
• Marx — thought’s “decidedness” a practical question
• Louis de Broglie; Tinbergen’s wasp experiment; Riley’s article on Schoenberg; Norman Rockwell
• Shakespeare, Comedy of Errors; Plautus; Menander; Homer and Virgil
• Aquinas’s commentary on Physics I, lectio 10–11 (verified source, probably)

His questions #

• Isn’t energy an accident rather than a substance? In physics it looks like a mover, but since mass is generated from it, it is treated as the source of matter, “substance” meaning matter.
• Do you agree with Einstein that matter is condensed energy? Mass is not conserved but energy is, so mass is subordinate to energy; but these words are measured quantities, not our “matter” and “mover.”
• Why did the Bohr atom force a change in the picture? Emission was jump-like, not continuous, so an orbit change could not be a change of place.
• “What are you reducing to order?” (Bohr) Our experience, taken as it stands — unlike Aristotle, who finds an order in things; whether that is all the scientists do is left open.
• What follows if man knows only what he makes? He is the beginning and end of all he knows, “God to himself,” enclosed in an inferior world, and driven crazy.
• How do you know the diameter bisects a circle? Thales’ way: if the halves do not coincide the radii are unequal; and the radii are equal because the circle is made by rotating a line about an endpoint.
• Is Kant exaggerating — don’t experiments still try to see something in nature? (student) Yes; “there may be some exaggeration,” but the physicists do say it, and if it is one’s only knowledge the mind is closed.
• Does truth require that the way we know be the way things are? If yes and we know by making, we know only what we make; but an experiment may show something apart from the experiment — left there.