Department of History
University of California, Irvine
 Instructor:    Dr. Barbara J. Becker

Week 4.  Galileo.

excerpts from
The Ash Wednesday Supper (1584)
by Giordano Bruno (1548-1600)


Described in Five Dialogues,
through Four Interlocutors,
with Three Considerations,
on Two Subjects.

Prefatory Epistle Written to
The Most Illustrious and Excellent
Seigneur de Mauvissiere

Chevalier of the King's Order, and Councillor in his Privy Council, Captain of fifty men at arms, Governor General of Saint Disidero, and Ambassador of France in England.

Here I offer you, my Lord, ... a repast so grand and small, so magisterial and schoolish, so sacrilegeous and religious, so cheerful and angry, so bitter and happy, so Florentine-lean and Bolognese-fat, so cynical and luxurious, so trifling and serious, so grave and clownish, so tragic and comical.  Thus, I am convinced that you will have not a few opportunities to be heroic and dejected, teacher and student, believer and unbeliever, happy and sad, saturnine and jovial, facile and ponderous, cringing and liberal, apish and dignified, a sophist with Aristotle, a philosopher with Pythagoras, smiling with Democritus, crying with Heraclitus.  I dare say that after you have sniffed with the Peripatetics, eaten with the Pythagoreans, drunk with the Stoics, you still may suck with the one who, in showing his teeth, displayed such a friendly smile as to reach both his ears with his mouth.  Therefore, as your bones are shaken and your marrow sapped, you will come on things that would distract a Saint Colombini..., would dazzle any merchant, would make the apes burst with laughter, and would break the silence of any graveyard.

You would ask, what symposium, what repast is this?  It is a supper.

What supper?  The supper of ashes.

What does it say, this supper of ashes?  Was perhaps such a meal served you before?  Or might one perhaps utter here [the words] Cinerem tamquam panem manducaram [I ate ashes like bread]?  No.

But it is a repast, taken after sunset, on the first day of Lent, called by our priests Ash Wednesday, and sometimes the day of memento.

What is that repast, that meal about?...

It is ... about one's intent to see to what extent nature can produce two fantastic goblins, two dreams, two shadows and two four-day fevers; and while the historical sense is being sifted, tasted and masticated, there will be submitted propositions, some topographical, others geographical, some rational, others moral.  Also speculations, some of which are metaphysical, others mathematical, others physical.



Smith [a curious and interested Englishman who is open to new ideas]
Theophil, philosopher [close friend of and spokesman for Giordano Bruno]
Prudenzio, pedant [voice of intellectual conservatism]
Frulla [Prudenzio's sometimes impudent student]
THE.  A few days past two [emissaries] came to the Nolan [Giordano Bruno of Nola, Italy] on behalf of a royal [attendant] letting him know how much he longed to converse with him so that he could understand his Copernicus and other paradoxes of the new philosophy.
[NOTE:  the two emissaries are cast as professors from Oxford named "Nundinio" and "Torquato."  The character of Nundinio may represent John Underhill (c.1545-1592) who was chaplain to Queen Elizabeth I, and bishop of Oxford from 1589.  Torquato may represent George Turner (1569-1610) who was associated with the Royal College of Physicians.]
[T]he Nolan replied that he does not see either with the eyes of Copernicus, nor with those of Ptolemy, but with his own as far as judgment and conclusions are concerned.

True, [he acknowledged that] in regard to observations he owed much to these and other industrious mathematicians who, from time to time, successively adding light to light, have established sufficient principles that enable us to make [our own] judgment, which can form itself only after long periods of study.  He added that those are in fact like the interpreters who translate words from one language to another, but then there are others who fathom the meanings and not the words themselves.  The former are like those peasants who report the trends and patterns of a skirmish to a distant captain; they themselves do not understand the steps, the reasons and the art by which they became victorious; but this is understood by the one who has the experience and better judgment in military matters....

Similarly with us; for how could we make a judgment if the many and diverse verifications of the appearances [perceived motions] of the higher and lower celestial bodies had not been clarified and placed before the eyes of reason?  [This would] certainly not [be possible].  Nevertheless, after having rendered our debts to those distributors of gifts which came from the first, infinitely omnipotent light, and having praised the studies of those generous spirits, we shall amply recognize that we should open our eyes at what they observed and saw, and should not give our consent to what they conceived, meant, and set forth.

SMI.  Please, let me know, what is your opinion of Copernicus?

THE.  He was possessed of a grave, elaborate, careful, and mature mind; a man who was not inferior, except by succession of place and time, to any astronomer who had been before him; a man who in regard to natural judgment was far superior to Ptolemy, Hipparchus, Eudoxus, and all the others who walked in the footsteps of these; a man who had to liberate himself from some false presuppositions of the common and commonly accepted philosophy, or perhaps I should say, blindness.

But for all that he did not move too much beyond them; being more intent on the study of mathematics than of nature, he was not able to go deep enough and penetrate beyond the point of removing from the way the stumps of inconvenient and vain principles, so as to resolve completely the difficult objections, and to free both himself and others from so many vain investigations, and to set attention firmly on things constant and certain.

For all that, who can fully praise the great mind of that German [oops!  Copernicus was, in fact, a Pole], who with little concern for the foolish multitude, stood solidly against the torrent of the opposite persuasion?  And though deprived of effective reasons, he seized those rejected and rusty fragments which he could have from the hands of antiquity, and repolished, matched and cemented them to such an extent with his more mathematical than physical discourse, that there arose the argument once ridiculed, rejected and vilified, but now respected, appreciated and possessed of greater likelihood than its contrary, and certainly more convenient and useful for theory and for computational purposes.

Thus this German, though he did not have sufficient means to become able not only to thwart, but also to fight, to vanquish, and to suppress sufficiently the falsehood [that the earth is immobile in a closed, finite universe], had nevertheless firmly made his stand to decide it in his soul and to confess it most openly, so that in the end one had of necessity to conclude that this globe moved with respect to the universe; rather than that it should be possible that the universality of so many innumerable bodies, of which many are known to be more magnificent and grand, should acknowledge this [globe of ours] as their center and the base of their gyrations and influences, in an insult to nature and to reason which with most evident motions loudly declare the contrary.

Who will, therefore, be so nasty and discourteous toward the work of that man as to forget both what he has done and his very being, destined by the gods to be that dawn which was to precede the rising of the sun of the ancient and true philosophy, buried for so many centuries in the dark caverns of blind, malicious, arrogant and envious ignorance, and to remember him by what he could not do, and to put him among the number of the herdlike crowd which moves, follows and rushes on by lending ear to a brutish and ignoble persuasion, rather than to count him among those who with a happy genius could rise and elevate themselves under the most reliable guidance of the eye of divine intelligence?

Now, what shall I say of the Nolan?  Would it perhaps be improper that I should praise him, just because he is as close to me as I am to myself?....

[I]f in our times Columbus is to be celebrated for being the one about whom it had been foretold long ago:

there will come an age
In the far-off years, when the Ocean
Shall unloose the bonds of things,
And a big land shall emerge, while Tiphys [Tethys]
Will disclose new realms, and Thule
Shall no longer be the limit of dry land,
then what is to be done about the one who found again the way to scale the skies, to make a tour of the spheres, of the planets, and leave behind the convex surface of the firmament?...

The Nolan, to achieve wholly opposite results, [has] set free the human spirit and cognition which was retained in the narrow prison of the turbulent [earthly] air, from where as if through some holes it could contemplate the most distant stars; its wings were cut lest it should fly and open the veil of these clouds, to see what is really there, and liberate itself of the chimeras of those who, though originating from the mud and caves of the earth, filled, as if they were Mercuries and Appollinos coming from heaven, the whole earth through many a swindle with endless folly, beastliness, and vice, as if with as much virtue, piety, and discipline, crushing that light which turned the souls of our ancestors divine and heroic, by approving and confirming the cloudy darkness of the sophists and jackasses....

Now here is he who has pierced the air, penetrated the sky, toured the realm of stars, traversed the boundaries of the world, dissipated the fictitious walls of the first, eighth, ninth, tenth spheres, and whatever else might have been attached to these by the devices of vain mathematicians and by the blind vision of popular philosophers.  Thus aided by the fullness of sense and reason, lie opened with the key of most industrious inquiry those enclosures of truth that can be opened to us at all, by presenting naked the shrouded and veiled nature; he gave eyes to moles, illumined the blind who cannot fix their eyes and admire their own images in so many mirrors which surround them from every side.

He untied the tongue of the mute who do not know [how to] and did not dare to express their intricate sentiments.  He restored strength to the lame who were unable to make that progress in spirit which the ignoble and dissolvable compound [body] cannot make.  He provided them with no less a [vantage point] than if they were the very inhabitants of the sun, of the moon, and of other nomadic stars [planets].  He showed how similar or dissimilar, greater or [smaller] are those bodies [stars, planets] which we see afar, compared with that which is right here [the Earth] and to which we are united.  And he opened their eyes to see this deity, this mother of ours, which on her back feeds them and nourishes them after she has produced them from her bosom into which she always gathers them again--who is not to be considered a body without soul and life, let alone the trash of all bodily substances.

In this way we know that, if we were on the moon or on other stars [planets], we would not be in a place much unlike this, and perhaps on an even worse [place], just as there may be other bodies as good and even better for their own sakes and for the happiness of their own [inhabitants].  Thus we know as many planets, as many stars, as many deities, which are those hundreds of thousands that assist in the service and contemplation of the first, universal and eternal efficient [cause].

Our mind is no longer imprisoned in the fetters of the imaginary movables and movers, eight, nine and ten.

[NOTE:  In the Ptolemaic system, the eighth sphere is that of the fixed stars; the ninth sphere is the so-called empyrean sphere--the realm of pure fire, the abode of God; the tenth sphere is the Prime Mover.]
We know that there is but one heaven, an eternal, immense region, where these magnificent lights keep their proper distances for a commodious sharing in a perpetual life.  These blazing bodies are those ambassadors that announce the excellence of God's glory and majesty.  Thus we shall advance to the discovery of the infinite effect of the infinite cause, the true and living evidence of the infinite vigor....

[T]his burden [of the new cosmology] cannot be placed on the shoulders of anyone except of those who can carry it, like the Nolan; or [of such] who can at least move it toward its target, as Copernicus was able to do, without incurring too great a difficulty....

PRU.  Be it as it may, I do not wish to part with the view of the ancients, for as the sage says, wisdom is with antiquity.

THE.  And the sage adds that prudence is to be found in [a past of] many years.  If you attend well to what you say, you will see that from your position there follows the very opposite of what you think.  I want to say that we are older, and have greater age than our predecessors, and by this I mean that [information] which enters in certain judgments as in this topic of ours.  The judgment of Eudoxus,  who lived only shortly after the rebirth of astronomy, if indeed it was not reborn in him, could not be so mature as the judgment of Calippus living thirty years after the death of Alexander the Great, who adding years to years could add observations to observations.  For the same reason, Hipparchus had to know more than Calippus, for he [had a record of] the changes [in the motion of the planets] for at least 190 years after the death of Alexander.  Menelaus, the Roman geometer, by [having a record of] the changes in [celestial] motions 460 years after Alexander's death, had reason [to think] that he understood more than Hipparchus.  Of those changes more could be [reviewed] by the Moslem Saracen [al-Battani (c. 858-c.929)] 1202 years after that.

Almost in our times, Copernicus [knew] even more of those changes, being separated from Alexander's death by 1849 years.  But some of those who have been closer to us did not become more judicious than those who had preceded them, and the multitude of our contemporaries has no more insight either; this happens because the former did not live and the latter do not [re-]live the years of others and (what is even worse) both the former and the latter lived as if dead through their own years.

PRU.  Say what you please, proceed anywhere to your high pleasure, I am a friend of antiquity, and concerning your opinions and paradoxes I do not believe that so many and so wise remained ignorant, as you think and do other friends, of novelties.

THE.  All right, Master Prudenzio, if this common opinion which is also yours is true inasmuch as it is antique, then it was certainly false when new....  Let us therefore put aside this argument of the old and of the new, because clearly there is nothing new that cannot become old, and nothing old that has not been new, as was well noted by your Aristotle.

FRU.  If I do not speak out, I will certainly burst apart and crack up.  You have said, 'your Aristotle' in talking to Master Prudenzio....  [T]here are many Peripatetics who grow angry, excited and inflamed on behalf of Aristotle, want to defend the doctrine of Aristotle, wish to live and die for Aristotle, who do not even understand what is meant by the titles of the books of Aristotle.  If you wish that I should show you one:  there he is, the one to whom you have said 'your Aristotle'....

PRU.  I do not really care to take into account what counts with you, and I have no use for your opinion.

THE.  Please, do not interrupt our discourse any more.

SMI.  Go on, Signor Theophil.

THE.  ...[T]o appraise the various philosophies by their antiquity is to try to decide whether the day or the night came first.  Therefore, what should be considered above all is whether we are in the daylight, and whether the sun of truth is over our horizon, or over the horizon of our antipodal opponents, whether we are in darkness or they, and finally, whether we, who give start to the revival of ancient philosophy, are in the morning to end the night, or in the evening to end the day?...

SMI.  Still, as a rule, one sticks to the common opinion, so that if one makes an error, one will not be without broad approval and consent.

THE.  A thought most unworthy of man.  This is why the learned and divine men are rather small in number, and this is so by the will of the gods, for nothing is, indeed, esteemed or valued unless it is [not] common and general.

SMI.  I readily believe that the truth is known by a few and that precious things are possessed by a very few.  Still, it puzzles me that many things are rare, and can only be found in the possession of a few, or perhaps of a single person, though they should not be valued and have no value, and may in fact be real madness and vice.

THE.  Very well; but in the end it is safer and more convenient to look for the truth away from the crowd...

SMI.  Let us, therefore, leave these topics, and let us stop for a while to hear and consider the thoughts of the Nolan.  It is no small matter that by now he has earned so much trust as to be considered worthy of being heard....

End of the First Dialogue


THE.  I ... wish to explain to you what we said, namely, that Copernicus presumably was not of the opinion that the earth moved, for this is inconvenient and impossible; but that he attributed such motion to the earth rather than to the eighth sphere for the sake of easier calculations.  The Nolan said that if Copernicus had said the earth moved for this sole reason and not for some other, then he understood little and hardly enough of Copernicus.  But it is certain that Copernicus meant it as he said it, and proved it with all his efforts.

SMI.  Would this mean that those vainly pass this judgment on Copernicus' opinion unless they can gather it from some propositions of his?

THE.  Note that such a statement comes from Doctor Torquato who from the whole Copernicus (though I may believe that he turned all its pages) retained only the name of the author, of the book, of the printer, of the place where it was printed, the year, the number of signatures and pages, and since he was not unfamiliar with [Latin], he understood a certain epistle attached to it by I do not know what ignorant and presumptuous jackass [Andreas Osiander] who (as if trying to support the author by exculpating him, or perhaps to enable other jackasses to find in this book their herbs and fruits, and not to let them part with it starving) adverted them in this way before they started reading the book and mulled over its phrases:

'I have no doubt that some savants ... feel greatly offended, because of the widespread publicity of the new suppositions of this work which wants the earth to be mobile and the sun to stand firmly set in the center of the universe, thinking that this is a cause to throw into confusion the liberal arts which had been well settled and for so long a time.  But if they wish to consider the matter more carefully, they will find that this author [Copernicus] is not deserving of blame, because it is the business of astronomers to gather diligently and artfully the history of celestial motions:  [and if they are] unable to find for some reasons the true causes of those motions, it is allowed to them to feign and formulate in their places reasons with the principles of geometry, by means of which [those motions] might be calculated both for the past and for the future[:]  therefore, not only is it not necessary that the suppositions should be true, but not even [that they should be] likely.

Such should [indeed] be esteemed the hypotheses of that man [Copernicus], except if someone were to be so ignorant of optics and geometry as to believe that the forty degrees or more acquired by Venus in receding from the sun on one side and the other is caused by its motion on its epicycle.  Were this the case, who would be so blind as not to see that which would follow from this against all experience:  that the diameter of the planet would appear four times larger, and the body of the planet more than sixteen times larger, when it is closest ... than when it is farthest away....'

[And he concludes in the end].
'Let us, therefore, take the treasure of these suppositions, solely for the marvelous and artificial facility of computations:  for, if someone would take as true these feigned things, he would exit more stupid from this science than when he entered.'

[NOTE:  On the Revolutions... opens with a foreword addressed to the reader followed by a preface and dedication to Pope Paul III.  For many years it was simply (and quite logically) assumed that Copernicus had written them both.  But careful readers weren't so sure:  the words in the foreword contradict those in the preface!  Years later, German mathematician Johannes Kepler (1571-1630) investigated the matter and unveiled the foreword's mystery author:  Andreas Osiander, a Lutheran theologian who, in the final stages of the book's prolonged publication process, had assumed full responsibility for seeing it through the press.  Bruno likens Osiander to an inept doorman who gives arriving guests a false impression of his master's house.]

Now, look, what a fine doorman!  See how well he opens the door for you to let you enter into the sharing of that most excellent knowledge [the motion of the earth], without which the art of doing computations, measurements, geometry and perspective is nothing else than the pastime of ingenious fools!  See how faithfully he serves the owner of the house [the author, Copernicus]!

To Copernicus it was not enough to say merely that the earth moves, but he also emphasizes and confirms it by writing to the Pope [Pope Paul III], and by saying that the opinions of the philosophers are very far from those of ordinary folks, which are unworthy of being followed and worthy of being avoided as the very opposite to what is true and right.  And many other explicit indications emerge from his [Copernicus'] statement, in spite of the fact that somehow in the end he seems to suggest, according to the opinion of both those who profess that philosophy [the motion of the earth], and of those who are pure mathematicians, that should such a supposition be declined because of the apparent inconveniences, then it is fitting that he too should be given the liberty of positing the motion of the earth in order to produce demonstrations that are more solid than those made by the ancients, who were free to feign so many kinds and models of circles to demonstrate the phenomena of the stars [planets].

From those words one cannot gather that he doubted what he so steadily professed and was to prove sufficiently in the first book [of On the Revolutions...] by replying to some arguments of those who held the opposite; there he resorts not only to the position of the mathematician who makes suppositions, but also to that of the physicist who proves the motion of the earth.

But certainly it counts little with the Nolan that Copernicus ... and other certainly very rare individuals, have said, taught and confirmed it beforehand; because he [the Nolan] holds it for other specific and more solid principles by which, not through authority but through real evidence and reason, he has this for as certain as anything else that can be had for certain.

SMI.  Very well; but, please, what is that argument which is offered by that doorman of Copernicus; for it appears to him that there is more than mere likelihood (if it indeed is not simply true) that the planet Venus should display as great differences in size as in distance.

THE.  That fool [Osiander] who passionately fears, lest some be duped by the doctrine of Copernicus,--I wonder if a more inept point could have been offered for a particular need than the one which he set forth with so much solemnity,--deems it sufficient to prove that to assume this [the variation in Venus' size] would be the act of one very ignorant about optics and geometry.  I would like to know what kind of optics and geometry is meant by that beast [Osiander], who shows all too well how ignorant he was about true optics and geometry, and were all those from whom he learned....

Nundinio submitted some argument ... namely, that if the earth were carried in the direction called east; it would be necessary that the clouds in the air should always appear moving toward west, because of the extremely rapid and fast motion of that globe, which in the span of twenty-four hours must complete such a great revolution.  To that the Nolan replied that this air through which the clouds and winds move are parts of the earth, because he wants (as the proposition demands) to mean under the name of earth the whole machinery and the entire animated part[:]  so that the rivers, the rocks, the seas, the whole vaporous and turbulent air, which is enclosed within the highest moutains, should belong to the earth as its members, just as the air [does] in the lungs and in other cavities of animals by which they breathe....

SMI.  You ... have replied to the argument taken from winds and clouds; there remains yet the reply to the other [argument] which Aristotle submitted in the second book of On the Heavens, where he states that it would be impossible that a stone thrown high up could come down along the same perpendicular straight line, but that it would be necessary that the exceedingly fast motion of the earth should leave it far behind toward the west.  Therefore, given this projection [back] into the earth, it is necessary that with its motion there should come a change in all relations of straightness and obliquity; just as there is a difference between the motion of the ship and the motion of those things that are on the ship which if not true it would follow that when the ship moves across the sea one could never draw something along a straight line from one of its corners to the other, and that it would not be possible for one to make a jump and return with his feet to the point from where he took off.

THE.  With the earth move, therefore, all things that are on the earth.  If, therefore, from a point outside the earth something were thrown upon the earth, it would lose, because of the latter's motion, its straightness as would be seen on [a] ship ... moving along a river, if someone on ... the riverbank were to throw a stone along a straight line, [and] would see the stone miss its course [target] by the amount of the velocity of the [ship's] motion.

But if someone were placed high on the mast of that ship, move as it may however fast, he would not miss his target at all, so that the stone or some other heavy thing thrown downward would not come along a straight line from the ... top of the mast, or cage, to the ... bottom of the mast, or at some point in the bowels and body of the ship.  Thus, if ... someone who is inside the ship would throw a stone straight [up], it would return to the bottom along the same line however far the ship moved, provided it was not subject to any pitch and roll....

If there are two, of which one is inside the ship that moves and the other outside it, of which both one and the other have their hands at the same point of the air, and if at the same place and time one and the other let a stone fall without giving it any push, the stone of the former would, without a moment's loss and without deviating from its path, go to the prefixed place, and that of the second would find itself carried backward.  This is due to nothing else except to the fact that the stone which leaves the hand of the one supported by the ship, and consequently moves with its motion, has such an impressed virtue [impetus], which is not had by the other who is outside the ship, because the stones have the same gravity, the same intervening air, if they depart (if this is possible) from the same point, and arc given the same thrust.

From that difference we cannot draw any other explanation except that the things which are affixed to the ship, and belong to it in some such way, move with it:  and one of the stones carries with itself the virtue [impetus] of the mover which moves with the ship.  The other does not have the said participation.  From this it can evidently be seen that the ability to go straight comes not from the point of motion where one starts, nor from the point where one ends, nor from the medium through which one moves, but from the efficiency of the originally impressed virtue, on which depends the whole difference....

End of the Third Dialogue


THE.  ...As all rose from table, there were some who in their own language [English] accused the Nolan of being impatient....  Nevertheless, the Nolan, who believes in outdoing in courtesy those who can easily outdo him in [some] other [matter], controlled himself, and as if he had forgotten about everything, he said amicably to Torquato:

Do not think, dear brother, that because of your views I want to or may become your enemy; nay, I am as much a friend of yours as of myself.  So that I want you to know that before taking this position as a most certain one, I held it several years ago as simply true; when I was younger and less knowledgeable, I held it as something very likely.  When I was more of a beginner in speculative things, I held it so factually false that I wondered at Aristotle that not only did he not disdain to consider it, but spent more than half of the second book, [of] On the Heavens, in an effort to demonstrate that the earth does not move.  When I was a kid, and acted without speculative thinking, I held that to believe this [the motion of the earth] was sheer madness and thought that it was advanced by some for the sake of sophistry and captious material [topic], and for the exercise of those carefree minds, who wish to dispute for game's sake, and who make a sport of proving and defending that white is black.

Therefore, I can hate you for this reason only as much as myself, insofar as I was younger, more childish, less wise, and less [discerning].  Thus, instead of being obligated to be angry with you, I have compassion for you, and I pray God that just as He gave me this knowledge, so (if it does not please him to make you capable of seeing it), He may at least make you capable of admitting that you are blind.  And this will be of no small help, to make you more polite, and courteous, less ignorant and brazen.  And you should still love me if not as one who is at present more prudent and older, at least as one who was more ignorant and more juvenile when I was partly in my more tender years, than you are in your old age.  I want to say that although I have never conversed and disputed in such a boorish, rude and discourteous manner, nevertheless for a while I was as ignorant as you.  Thus, I have consideration for your present state, [which is] similar to my past state, and you for my past state, similar to your present state, [and so] I will love you and you do [should] not hate me....

Having concluded this discourse they [Torquato and Nundinio] began to consult among themselves in English, and after they spent some time together, there appeared on the table a sheet of paper and an inkwell.  Doctor Torquato spread it out until it made a wide and long page, took the pen in his hand, drew a straight line across the middle of the page from one side to the other; in the middle he drew a circle, to which the aforesaid line passing through the center formed a diameter and inside of one of its semicircles he wrote TERRA [earth], and inside the other semicircle he wrote SOL [sun].  On the side of the [semicircle of the] earth he drew eight semicircles, where the symbols of the seven planets were [placed] in order, and around the last [semicircle] there was written octava sphæra mobilis [eighth movable sphere] and on the margin PTOLOMÆUS.

Meanwhile the Nolan [asked] him what he wanted to do with that which even children know?

Torquato replied[:]  Vide, tace, et disce; ego docebo te Ptolomeum et Copernicum [Look, listen, and learn:  I will teach you Ptolemy and Copernicus]....

The Nolan replied that when one writes the alphabet, it is a poor method to wish to teach grammar to one who knows more of it than does the former.

Torquato went on making his diagram, and around the sun, which was in the middle, he drew seven semicircles with similar symbols, writing around the last one Sphæra immobilis fixarum [immobile sphere of the fixed stars], and on the margin:  COPERNICUS.

Then, he turned to the third circle, and on a point of its circumference he marked the center of an epicycle; having drawn its circumference, he painted in its center the globe of the earth and that no one should delude himself into thinking that it was not the earth, he wrote there in large characters, TERRA.  And on a point of the circumference of the epicycle, which was most distant from the center, he marked the symbol of the moon.

When the Nolan saw this, (he said) look, here he wants to teach me from Copernicus what Copernicus himself did not mean, and would rather have had his head cut off than to say it or write it.  Because the biggest jackass on earth would know that from that part one would always see the diameter of the sun [the same] and other numerous conclusions would follow that cannot be verified.

Tace, tace [Be quiet, be quiet], said Torquato, tu vis me docere Copernicum [you want to teach me Copernicus]?

I care little about Copernicus, said the Nolan, and I care little that you or others understand him; but I want to remind you of this alone, that before you come to instruct me another time, study better [the subject].

The gentlemen there present showed so much diligence that the book of Copernicus was brought in, and by looking at the figure they saw that the earth was not marked on the circumference of the epicycle as was the moon, so that Torquato wanted ... the point in the center of the epicycle on the circumference of the third sphere [to designate] the earth.

The system of the world, from On the Revolutions....  Who has interpreted Copernicus correctly--Torquato or Bruno?

SMI.  The cause of the error was that Torquato has studied the figures in that book [On the Revolutions...], and has not read the chapters and even if he had, he did not understand them.

THE.  The Nolan began to laugh and told him that this point represented no other thing than the [fixed] point of the compass as it traced out the epicycle of the earth, and of the moon which is one and the same.  Or if you truly wish to know where the earth is according to the meaning of Copernicus:  read his own words.

They read and found that the earth and the moon were as if carried by the same epicycle, etc.  And so they kept ruminating in their own language, until Nundinio and Torquato departed, having greeted all the others except the Nolan....

Those [remaining begged] the Nolan that he should not be upset because of the discourteous impoliteness and brazen ignorance of their doctors; but that he should have compassion over the poverty of this country, which was left a widow by [learning] concerning philosophy and real mathematics [astronomy] (in which they are now all like blind men; [so] there come these jackasses and present themselves as seers...), they left him with most polite salutations and went on their way; we and the Nolan returned home late along another route....

End of the Fourth Dialogue

Go to:
  • A Perfit Description of the Celestiall Orbs... (1576), by Thomas Digges (c.1546-1595)
  • Conversation with the Sidereal Messenger (1610), by Johannes Kepler (1571-1630)
  • Dialogue Concerning the Two Chief World Systems(1632), by Galileo Galilei (1564-1642)
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