leonardo from larouche’s standpoint: the principle of ... · 87 f or five hundred years, the...

5
87 F or five hundred years, the writings and discoveries of Leonardo da Vinci have been dispersed and put through “the shredder,” his paintings mutilated and lost, by an oligarchy determined to stamp out every vestige of his method of creative discovery. At least two-thirds, perhaps more than three-fourths, of his legacy has vanished. Yet, every so often, someone discovers a new truth about the great scientist- artist, which stuns the Aristotelians. In 1965, there was the fabulous rediscovery, in the Biblioteca Nacional in Spain, of what are now called the Madrid Codices —two notebooks filled with drawings and investigations of technology, hydrodynamics, military science, and many other domains of knowledge. The Codex had languished on the library shelf, lost to the world for 135 years, because of confusion in the library’s filing system. Now, a new discovery: Geologist Ann Pizzorusso, in a lecture at the American Museum of Natural History in November of last year, presented convincing proof concerning an ongoing sus- picion amongst art histori- ans that, of the two versions of Leonardo’s “The Virgin of the Rocks,” the London one was not painted by Leonardo (the two versions are at the Louvre in Paris, and the National Gallery in London). Or rather, at least not all of it was painted by Leonardo. Pizzorusso’s pre- sentation was part of a lec- ture series held in conjunc- tion with the Museum’s Oct. 26, 1996–Jan. 1, 1997 exhibition of Leonar- do’s Codex Leicester. It seems that for five hundred years, when people looked at the paintings, they looked at the Virgins; now, some- body has looked at the rocks. Pizzorus- so’s findings are quite startling. Whereas the geological accuracy of the rock for- mations in the Louvre painting is, she says, “astounding . . . a geological tour de force,” the rocks in the London version are “synthetic, stilted, grotesque charac- terizations.” Further, in the Louvre ver- sion, the vegetation is appropriate to the setting and is found among only those rocks where such plants could actually grow, whereas in the London painting, the plants are arranged arbitrarily and “resemble cultivated annuals need- ing considerably more light than would be available in the grot- to.” 1 [SEE Diagram, pp. 88-89] Pizzorusso notes Leo- nardo’s sensitivity to the portrayal of landscapes, and his objection to those artists, such as Botticelli, who painted “very bad landscapes,” as mere back- drops for human figures. Wrote Leonardo, a “painter is not well-rounded who does not have an equally keen interest in all things within the compass of painting.” Why is Pizzorusso’s finding so interesting? Why did Leonardo think the landscapes were worth so much bother? This gets to the core issue of da Vinci’s importance as a scientist. Five centuries of misin- terpretation have attempted to brand Leonardo an “empiricist.” Martin Kemp, in his essay in the catalogue of the Codex Leicester exhi- bition, concedes only that Leonardo’s “empiricism” was “tempered by the role he assigned to deductive reasoning.” 2 Ivor Hart, in Leonardo from LaRouche’s Standpoint: The Principle of Least Action COMMENTARY Leonardo da Vinci, “Virgin of the Rocks” (Louvre version), 1483-86. © RMN, Louvre Click here for Full Issue of Fidelio Volume 6, Number 1, Spring 1997 © 1997 Schiller Institute, Inc. All Rights Reserved. Reproduction in whole or in part without permission strictly prohibited.

Upload: phamnguyet

Post on 25-Apr-2018

215 views

Category:

Documents


1 download

TRANSCRIPT

87

For five hundred years, the writingsand discoveries of Leonardo da

Vinci have been dispersed and putthrough “the shredder,” his paintingsmutilated and lost, by an oligarchydetermined to stamp out every vestige ofhis method of creative discovery. Atleast two-thirds, perhaps more thanthree-fourths, of his legacy has vanished.Yet, every so often, someone discovers anew truth about the great scientist-artist, which stuns the Aristotelians.In 1965, there was the fabulousrediscovery, in the BibliotecaNacional in Spain, of what arenow called the MadridCodices—two notebooksfilled with drawings andinvestigations of technology,hydrodynamics, militaryscience, and many otherdomains of knowledge. TheCodex had languished onthe library shelf, lost to theworld for 135 years, becauseof confusion in the library’sfiling system.

Now, a new discovery:Geologist Ann Pizzorusso,in a lecture at the AmericanMuseum of Natural Historyin November of last year,presented convincing proofconcerning an ongoing sus-picion amongst art histori-ans that, of the two versionsof Leonardo’s “The Virginof the Rocks,” the Londonone was not painted byLeonardo (the two versionsare at the Louvre in Paris,and the National Gallery inLondon). Or rather, at leastnot all of it was painted byLeonardo. Pizzorusso’s pre-sentation was part of a lec-ture series held in conjunc-

tion with the Museum’s Oct. 26,1996–Jan. 1, 1997 exhibition of Leonar-do’s Codex Leicester.

It seems that for five hundred years,when people looked at the paintings,they looked at the Virgins; now, some-body has looked at the rocks. Pizzorus-so’s findings are quite startling. Whereas

the geological accuracy of the rock for-mations in the Louvre painting is, shesays, “astounding . . . a geological tour deforce,” the rocks in the London versionare “synthetic, stilted, grotesque charac-terizations.” Further, in the Louvre ver-sion, the vegetation is appropriate to thesetting and is found among only thoserocks where such plants could actuallygrow, whereas in the London painting,

the plants are arranged arbitrarily and“resemble cultivated annuals need-

ing considerably more light thanwould be available in the grot-

to.”1 [SEE Diagram, pp. 88-89]Pizzorusso notes Leo-

nardo’s sensitivity to theportrayal of landscapes, andhis objection to thoseartists, such as Botticelli,who painted “very badlandscapes,” as mere back-drops for human figures.Wrote Leonardo, a “painteris not well-rounded whodoes not have an equallykeen interest in all thingswithin the compass ofpainting.”

Why is Pizzorusso’sfinding so interesting? Whydid Leonardo think thelandscapes were worth somuch bother? This gets tothe core issue of da Vinci’simportance as a scientist.

Five centuries of misin-terpretation have attemptedto brand Leonardo an“empiricist.” Martin Kemp,in his essay in the catalogueof the Codex Leicester exhi-bition, concedes only thatLeonardo’s “empiricism”was “tempered by the rolehe assigned to deductivereasoning.”2 Ivor Hart, in

Leonardo from LaRouche’s Standpoint: The Principle of Least Action

COMM ENTARY

Leonardo da Vinci, “Virgin of the Rocks” (Louvre version), 1483-86.

©R

MN

,Lou

vre

Click here for Full Issue of Fidelio Volume 6, Number 1, Spring 1997

© 1997 Schiller Institute, Inc. All Rights Reserved. Reproduction in whole or in part without permission strictly prohibited.

88

his book on Leonardo, goes so far as todescribe Nicolaus of Cusa, the founderof Renaissance science who profoundlyinfluenced Leonardo, as a forerunner ofFrancis Bacon!3 According to such anidiotic view, Leonardo painted rocksaccurately because of his “realism.” In aword: “He painted them that way,because that’s the way they looked.” Or,as Aristotle had it: The purpose of art isto imitate nature.

In this brief article, I shall indicatewhy this is not the case, drawing uponthe in-depth treatment of the epistemo-logical issues provided in many worksby Lyndon H. LaRouche, Jr.4

Leonardo’s Conception of Physical Geometry

Contrary to the empiricists, Leonardoapproached the natural world from thestandpoint of the Platonic method ofhypothesis: looking beyond the Many—the predicated phenomena of the natur-al world—to conceptualize the One—the higher-order idea that generates andencompasses that diversity. Studying thegeometry of natural forms (whetherrocks, water, air, or living bodies), incollaboration with mathematician LucaPacioli, he sought to understand the wayin which the physical geometry of space-time bounds the patterns of naturalgrowth and development.

LaRouche has described the episte-mological current in history of whichLeonardo was a part: “[T]he literatureof modern physical science is dividedinto two camps. The first camp, whichfounded modern physical science interms of reference to Plato and Archi-medes (287-212 B.C.), is the school ofNicolaus of Cusa, Leonardo da Vinci,Johannes Kepler, G.W.F. Leibniz, Gas-pard Monge (1746-1818), Carl Gauss,and Bernhard Riemann, based upon the‘hereditary principle’ of synthetic physi-cal geometry. The second camp, whichinvaded the province of physical sciencefrom the outside, during the Seven-teenth century, about two hundredyears later, is based upon the ‘hereditaryprinciple’ of the deductive theorem-lat-tice. Although the literature of the twocamps often appears to coincide, oncloser scrutiny of both, there is an

unbridgeable gulf between the two.”5

It is that “hereditary principle of syn-thetic physical geometry” that holds thekey to Leonardo’s so-called landscapes,and the depiction of the geological for-mations in the Virgin’s grotto.

The breakthrough in the science ofperspective made during the Renais-sance by Leonardo and other artists,for the first time located geometryfirmly in the study of real physicalprocesses. From their investigations ofoptics and of how human beings per-ceive the world around them, theydeveloped an understanding of thelaws of perspective that went farbeyond the linear, Euclidean geometryof their predecessors.6

Compare the Earth-centered geo-metrical universe of hoaxster ClaudiusPtolemy, for example, who describedthe universe as a complex interactionof circles upon circles, to accountmathematically for the observed pathsof the celestial bodies. While Ptolemy’sgeometrical construct succeeded, up toa point, in describing the motions ofthe sun, moon, and planets, it wasnever even intended to be a descrip-tion of reality. The concatenated setsof epicycles, equants, and deferentsimposed by Ptolemy were neverassumed to have any physical reality,and no explanation was ever offered,

as to how this description might relateto the actual physical processes atwork. (Of course, it couldn’t!)

But, for Leonardo, mathematics—i.e., geometry—must describe realprocesses in space-time. It is therefore,necessarily, a description of change, ofcontinuing transformation. Startingwith the division of a spherical shell bymeans of the Golden Section (or whatLeonardo and Pacioli called “the DivineProportion”), to generate the five Pla-tonic solids, Leonardo would proceed toinvestigate the specific geometriesexpressed by both living and non-livingprocesses. He studied what happens to ashape, such as a triangle, when it isdeformed by wind, water, or other phys-ical process. He probed the geometry ofwave formation, founding the science ofhydrodynamics. His astronomical andoptical drawings, such as those in theCodex Leicester, were an attempt tounderstand how light actually behaves.This quest led him to two revolutionaryconceptions: (1) that light is propagatedat a finite rate, not instantaneously (twohundred years before Ole Rømer provedthis); and (2) that light is propagated bytransverse wave motion, not by “rays” oftiny particles (two hundred years beforeChristiaan Huyghens and JohannBernouilli elaborated this).7 The twoideas are related, since if light travels in

Diagram of the Louvre Virgin of the Rocks“From top to bottom: Rounded (spherically weathered) mounds of horizontally

layered (bedded) sandstone form the top of the grotto. The column of rock abovethe Virgin’s head is diabase, an igneous rock deposited on the sandstone as a

molten liquid. As it cooled, the diabase formed a layer of rock (a sill) and shrank involume. The contraction caused the rock to crack perpendicular to the sandstone,

forming columnar joints (fractures). The columnar joints in the painting are notperfectly vertical, but inclined slightly. This implies that the sandstone dips a few

degrees away from the observer, which is borne out by close study of the layers.Directly above the Virgin’s head is a horizontal line (basal contact) that separates

the diabase sill from the weathered sandstone below. The texture and roundedweathering pattern of the sandstone below the basal contact are the same as they

are at the top of the grotto. In the foreground, the sandstone is layered, or bedded,with the utmost accuracy. In the background, rocky towers, or pinnacles, rise froma blue-gray mist. These towers are remnants of erosional processes that strip away

the overlying softer rock and leave the more weather resistant, harder rock intact.” (Copyright © Ann Pizzorusso, reprinted with permission)

89

waves, it cannot propagate instanta-neously. Without the idea of the finiterate of propagation of light, there can beno scientific comprehension of optics—only Newtonian magic.

An Example: The Least-ActionPrinciple

The contribution of an outstandingindividual such as Leonardo is bestunderstood by looking at the current ofhuman thought from which it derives,“hereditarily,” and where it leads. Start-ing with Nicolaus of Cusa’s discovery ofthe Maximum-Minimum Principle, wework our way through the founding of

applied physics by Leonardo and Paci-oli, through Kepler’s establishment of acomprehensive mathematical physics,and on to the work of Leibniz, Gauss,Riemann, and LaRouche.

To understand Leonardo’s concep-tion of physical geometry, it is useful tolook at what LaRouche has called “theCusa-Leonardo-Kepler-Leibniz-Rie-mann definition of the Principle ofLeast Action.” (Actually, we needanother hyphen: “-LaRouche.” It is onlywith LaRouche’s contribution that thecontinuity of the work of the earlier fig-ures comes into clear focus.)

As Martin Kemp notes in the Codex

Leicester catalogue, Leonardo believedthat every phenomenon was constrainedto act in accordance with the laws ofnature, and that every form was designedto perform its function by the “shortestway.” But, these are none other thanLeibniz’s principles of necessary and suf-ficient reason and least action, two of themost important ideas in the history ofscience (although Kemp mentions themonly in passing, and does not identifythem by name). Indeed, two hundredyears before Leibniz, Leonardo wrote:“Every action in nature takes place inthe shortest way possible.”8

What is the least-action principle?Many lies have been told about this in thepast five hundred years. If you are an“Information Age” modern, and searchfor it on the Internet, you will find that itwas “stated for the first time by Pierre-Louis Moreau de Maupertuis (1698-1759)as ‘Nature is thrifty in all its actions.’”9

Thrifty? —“Thrift, thrift, Horatio!”said Hamlet, with reference to his moth-er’s marriage to her husband’s murder-er: “The funeral baked meats did coldlyfurnish forth the marriage tables.”

No, the least-action principle is not aquestion of thrift, although AdamSmith and the bankers of the City ofLondon might think so! It is a principleof creation. Leibniz described it as“God’s decree always to produce hiseffect by the simplest and most determi-nate ways.”10

In fact, Maupertuis stole the least-action principle from Leibniz, strippingit of its true scientific-epistemologicalcontent, and turning it into a calculusfor the later economics of Adam Smithand utilitarian philosophy of JeremyBentham.11 When his swindle wasexposed, he was defended by the Swissmathematician Leonhard Euler, whootherwise devoted his career to crushingthe influence of Leibniz.

From Cusa to LaRouche

To find the true origins of the least-action principle, we must begin withNicolaus of Cusa. By his proof of theimpossibility of “squaring” the circle, hemade possible the entire future develop-ment of mathematical physics. AsLaRouche writes,12 the crucial feature

90

was the “Maximum-Minimum” princi-ple, from which the isoperimetric prin-ciple of topology is derived, and alsoLeibniz’s principle of least action. Thecircle is the minimum form that enclosesthe maximum area.

Among the implications of Cusa’sisoperimetric principle, writes La-Rouche,13 are that (1) circular action is adistinct geometrical species of action inspace-time; and (2) it is defined as theleast action of closed perimetric displace-ment required to subtend the relativelylargest area. “Thus, the Fermat-Huyghens-Leibniz-Bernouilli principleof least action is already implicit,‘hereditarily,’ in Cusa’s discovery.”

Cusa’s work set the stage for the cru-cial discoveries of Pacioli and Leonardorespecting the importance of the GoldenSection. They showed that all livingprocesses are ordered harmonically,bounded by the Golden Section relation-ship, whereas non-living processes arenot. For living processes, the GoldenSection represents a least-action pathwayof growth and development.

In the same way, Leonardo investi-gated least-action pathways in waveand vortex formations in water. Inoptics, he explored the pathways of thepropagation of light, the formation ofcaustics, and which geometrical config-urations of lenses could eliminate the

caustic and allow a light beam to focus.“Then, with stunning force, comes

Kepler,” writes LaRouche.14

Reflecting on the work of Cusa,Pacioli, and Leonardo, Kepler com-ments that “there were three things inparticular about which I persistentlysought the reasons why they were suchand not otherwise: the number, thesize, and the motion of the circles[planetary orbits].”15 He discovers thatthe orbits of the planets are far fromarbitrary; they are determined by thecurvature of physical space-time itself,as reflected in the Platonic solids, har-monic musical proportions, and conicfunctions. (That is, he supplies a partic-ular sort of “why” missing in Ptolemy’sdescriptive construct.)

LaRouche emphasizes the aspect ofcurvature in Kepler’s work: “The addi-tional crucial feature of circular action,is that it defines our universe in terms ofboth negative and positive curvatures,with the demonstration that negativecurvature predominates. This point issummed up rather neatly in JohannesKepler’s 1611 booklet, On the Six-Cor-nered Snowflake. The snowflake is anon-living process determined by thefunction of positive curvature in deter-mining the close packing of sphericalbubbles. The negative curvature of theinterior of each and all bubbles deter-

mines structures ‘hereditarily’ coheringwith the five Platonic solids, and, thus,with the harmonic orderings coheringwith the Golden section of the circum-scribing sphere’s great circle.

“The universe can be considered aseverywhere superdensely packed withspherical bubbles of all imaginable radii,as the unique, bounding characteristic ofgeneralized ‘non-algebraic’ functionshows this to be necessarily the case. Bythe close of the seventeenth century, itwas implicitly demonstrated that thisbubbly universality of the least-actionprinciple is otherwise characterized bythe combined notions of electromagneticleast action and hydrodynamic forms ofsuch action. Thus, frequency of radia-tion is associated with a correspondingresonant set of bubbles—e.g., of corre-sponding radii.”16

Leibniz’s concepts of necessary andsufficient reason and least action derive,hereditarily, from Kepler’s work.

The first, Leibniz defines simply as“that nothing happens without it beingpossible for someone who knowsenough things to give a reason suffi-cient to determine why it is so and nototherwise.”17 This is the principleunderlying Kepler’s question, quotedabove, as to the number, size, and orbitsof the planets.18

The least-action principle is a special

Notes and observations from the “CodexLeicester.” Left: Obstacles affecting currents,and their use to prevent damage to riverbanks(detail, fol. 13B). Right: Movement of waterthrough narrow passages and under bridges(detail, fol. 9r). Below: Siphons and centers inthe sphere of water (detail, fol. 34v).

American Museum of Natural History

American Museum of Natural History

American Museum of Natural History

91

case of the principle of necessary andsufficient reason. As Leibniz explains:“It follows from the supreme perfectionof God that he chose the best possibleplan in producing the universe, a plan inwhich there is the greatest varietytogether with the greatest order. Themost carefully used plot of ground,place, and time; the greatest effect pro-duced by the simplest means; the mostpower, knowledge, happiness, andgoodness in created things that the uni-verse could allow. For, since all the pos-sibles have a claim to existence in God’sunderstanding in proportion to theirperfections, the result of all these claimsmust be the most perfect actual worldpossible. And without this, it would notbe possible to give a reason for why thingshave turned out in this way rather thanotherwise.”19 [Emphasis added]

Now, returning to the Virgin of theRocks after this quick tour through thehistory of ideas, we are better situated tolook at the “landscape” through Leonar-do’s eyes. He wonders about the process-es that long ago formed the diverse vari-eties of rocks in the grotto. At the top ofthe cave, in the Louvre painting, reportsPizzorusso, are mounds of sandstone, asedimentary rock. It has crumbled suffi-ciently to allow the roots of plants togrow. Above the Virgin’s head is dia-base, an igneous rock. No plants growhere—it is too hard and resistant to ero-sion. Directly above the Virgin’s head isa horizontal crack in the rocks, called abasal or bottom contact—the seambetween the diabase above and anotherlayer of sandstone below.

In the Codex Leicester, Leonardopuzzles over how fossils of seashells andother creatures can be found at the topsof mountains. He rejects the theory thatthey were swept there by the turbulentbiblical Flood: If they had been, theywould all be a jumble, and yet, we findthem in orderly groups and colonies,just as they grow today. The mountainsmust, he writes, have been covered bystanding water at one time.

So, too, in the Louvre Virgin of theRocks, Leonardo asks: How did thiscome to be? He records his explorationof the processes, in physical geometry,which produced these geological forms.

The processes must result in the mostperfect actual world possible, a worldwhose perfection lies in the greatest pos-sible variety coupled with the greatestorder. The scientific exploration of thisplan of perfection is the reason why, forLeonardo, the painted landscapes are noless important than the human dramasman plays out upon them.

—Susan Welsh

1. Ann C. Pizzorusso, “Leonardo’s Geology:The Authenticity of the Virgin of theRocks,” Leonardo, Vol. 29, No. 3, 1996, pp.197-200. See also Pizzorusso, “The Natu-ralist Genius of Leonardo da Vinci,” TheExplorers Journal, Spring 1996, pp. 24-29.

2. Martin Kemp, “The Body of the Earth,” inLeonardo da Vinci, Codex Leicester: A Mas-terpiece of Science, ed. by Claire Farago(New York: American Museum of NaturalHistory, 1996). In his book Leonardo daVinci: The Marvelous Works of Man andNature (Cambridge, Mass.: Harvard Uni-versity Press, 1981), p. 139, he classifiesLeonardo as an Aristotelian.

3. The World of Leonardo da Vinci: Man of Sci-ence, Engineer, and Dreamer of Flight (NewYork: Viking Press, 1961), p. 142.

4. See, for example, Lyndon H. LaRouche,Jr., “Leibniz From Riemann’s Standpoint,”Fidelio, Fall 1996 (Vol. V, No. 3); “On theSubject of Metaphor,” Fidelio, Fall 1992(Vol. I, No. 3); In Defense of Common Sense,in The Science of Christian Economy andOther Prison Writings (Washington, D.C.:Schiller Institute, 1991); Cold Fusion: Chal-lenge to U.S. Science Policy (Washington,D.C.: Schiller Institute, August 1992); “WeMust Attack the Mathematicians to Solvethe Economic Crisis,” Fidelio, Fall 1995(Vol. IV, No. 3); See also Dino de Paoli,“Leonardo da Vinci and the True Methodof Magnetohydrodynamics,” Fusion, Janu-ary-February 1986; and Susan Welsh,“Leonardo’s ‘Leaps’: Metaphor and theProcess of Creative Discovery,” ExecutiveIntelligence Review, Nov. 29, 1996 (Vol. 23,No. 48).

5. LaRouche, Common Sense, op. cit., p. 36.6. See Karel Vereycken, “The Invention of

Perspective,” Fidelio, Winter 1996 (Vol. V,No. 4), pp. 46-67.

7. “Just as a stone thrown into water becomesthe center and cause of various circles,sound spreads in circles in the air. Thusevery body placed in the luminous airspreads out in circles and fills the sur-rounding space with infinite likenesses ofitself and appears all in all and all in everypart.”—Codex Atlanticus, folio 9v

“It is impossible that the eye should

project the visual power from itself, byvisual rays, since, as soon as it opens, thatfront portion [of the eye], which wouldgive rise to this emanation, would have togo forth to the object, and this it could notdo without time. And this being so, itcould not travel as high as the sun in amonth’s time when the eye wanted to seeit.”—Codex Ashburnham, 2038, folio 1r

Quoted by Domenico Argentieri,“Leonardo’s Optics,” in Istituto GeograficoDe Agostini, Leonardo da Vinci (NewYork: Reynal and Co., n.d.), p. 405, 407.

8. Quaderni d’Anatomia, IV, folio 16r, quotedby Argentieri, p. 410.

9. Gérard A. Langlet, “The Least ActionPrinciple (LAP) in APL,” www.demon.co.uk/apl385/apl96/gerard.htm

10. Discourse on Metaphysics, in G.W. Leibniz:Philosophical Essays, trans. by RogerAriew and Daniel Garber (Indianapolisand Cambridge: Hackett Publishing Co.,1989), p. 54.

11. In the Dictionary of Scientific Biography,biographer Bentley Glass quotes A.O.Lovejoy, that Maupertuis represents “theheadwaters of the important stream ofutilitarian influence through the work ofthe Benthamites.” Glass describes Mau-pertuis’ calculus of pleasure and pain, aproduct of intensity and duration, as“strictly analogous to his principle of leastaction in the physical world, and showshow he extended his philosophy ofnature into a philosophy of life.” Mau-pertuis belonged to the network ofEnlightenment ideologues organized bythe Abbé Conti; see Webster G. Tarpley,“Venice’s War Against Western Civiliza-tion,” Fidelio, Summer 1995 (Vol. IV,No. 2), p. 12.

12. LaRouche, Common Sense, op. cit., p. 29.13. LaRouche, “Metaphor,” op. cit., p. 20.14. LaRouche, Cold Fusion, op. cit., p. 29.15. Johannes Kepler, Mysterium Cosmograph-

icum (The Secret of the Universe), trans. byA.M. Duncan (New York: Abaris Books,1981), p. 63.

16. LaRouche, “Metaphor,” op. cit. pp. 21-22.17. “Principles of Nature and Grace, Based

on Reason,” in Ariew and Garber, op cit.,p. 210.

18. Compare this to the prevalent modernview, reflected in the statement ofFranklyn M. Branley, the former directorof New York’s Hayden Planetarium, in abook on astronomy for young people:“Why are there nine planets? . . . Thereappears to be no particular reason whyour system is made up of nine planets.”(Mysteries of the Planets [New York: E.P.Dutton, 1988], p. 8.)

19. Leibniz, “Nature and Grace,” in Ariewand Garber, op. cit., p. 210.