A History of Western Philosophy

Copernican Revolution

There is a standard interpretation of the Copernican Revolution and we will begin with this. But remember, in our lecture series we are trying to address the question of the origin and development of inequality and prejudice over two and half thousand years. This gives us the opportunity to place the Copernican Revolution, unusually, within the Great Chain of Being to see what effects it had on the ideas of hierarchy, plenitude, and continuity. 

If we are to understand the Copernican Revolution then we need to understand what it was a revolution of, or in. Alongside the theory of emanation as explaining the Great Chain of Being from God to human beings, and from form to matter, and from intellect to body and animal desire, there was a theory of movement or motion which explained observations of the positions and journeys of the stars in the heavens. We will take a quick tour through this aspect of celestial physics, or cosmology.

There were two pre-Copernican systems of the cosmos. One we have already seen was that of Aristotle, originally from Eudoxus and Callipus, of a system of concentric circles. We saw that it was thought of as something like this. 

Remember too that in Aristotle movement was either towards or away from the center, or circular. Circular movement was perfect. Hence circular heavens, or spheres. There is a prime mover, but Aristotle argued that each sphere must also be an eternal substance, and he discerned between 49-55 of them, having their own stars, made of ether, and each being its own god or self-moving principle. This explanation was required in order to explain the observable motion of the stars, or, as is said, ‘to save the appearances.[1] What was unacceptable was for theory not to fit what people could see for themselves, and so theory always had to find new ways to explain away any such discrepancies. 

The second cosmological model was much more influential and famous. It is the model we saw from Ptolemy in the Almagest.

His model is not concentric, but eccentric, trying to explain how the planets seemed to move with variable speeds and appearing at times to move backwards or in retrograde motion. He explained this in terms of epicycles where one planet was deemed to be orbiting another. It was an incredibly complex system, but again the theory did not exactly match what could be observed. In reference to saving the appearances, Ptolemy stated, ‘one should not reasonably think it strange or absurd to vary the mode of the hypotheses of the circles, especially when, along with saving the regular circular movement absolutely everywhere, each of the appearances is demonstrated in its more lawful and general character’ (Hutchins, 1952, 273; IX.2.)

But the complexity of the Ptolemaic model of epicycles led to some 40 or more wheels within wheels. 

A level of incredulity seems to have accompanied its general acceptance. For example, in Paradise Lost, Milton has the angel Raphael suggest that God must find it rather funny how, in trying to explain the cosmos to our own satisfaction, or within our own limited abilities, 

They come to model Heav’n

And calculate the stars, how they wield

The mighty frame, how build, unbuild, contrive

To save appearances, how gird the Sphere

With Centric and Eccentric scribbled o’er

Cycle and Epicycle, Orb in Orb     (Book VIII 76-82)

Remember, too, that the Ptolemaic system worked with Aristotelian physics. The planets still moved in perfect circles as their natural motion and the earth had its place, stationary, at the center of the universe. 

Some of this would change with so-called Copernican Revolution, arising just after the time of the Italian Renaissance, but greatly influenced by the Islamic Renaissance in Baghdad. 

The seminal year of 1543 saw the publication of Copernicus’s De revolutionibus orbium coelestium, or On The Revolutions of the Celestial Spheres

Let us note two things at the start. The spheres referred to in the title as those of Eudoxus and Aristotle.[2] And Copernicus introduced more epicycles to the cosmos than Ptolemy had done.[3] The Copernican Revolution still operated within the universe of concentric spheres; it did not overturn it.  So, what was the revolution here?

As is well known Copernicus put the sun at the center of the universe and moved the Earth to a sphere that orbited the sun. ‘We revolve around the Sun like any other planet’ he said in the earlier Commentariolus of 1514 (and only published in the 1800s). The order of the planets, or spheres, was Mercury, Venus, Earth, Moon, Mars, Jupiter and Saturn. He also said that the Earth rotated on its own axis every 24 hours, but in antiquity Heraclides of Pontus and Aristarchus had both suggested this, the latter also arguing that the earth orbited the sun.  Retrograde motion is also easily explained in Copernicus’s system by the relative speeds of the planets and the sun. And it meant that Copernicus could accurately predict the future positions in space of the planets. 

Before we look at the implications for the Great Chain of Being of the Copernican Revolution let us return to saving the appearances. So controversial, and heretical, was the revolutionibus that Copernicus withheld publication from all but a few astronomers. It was only published in 1543, the year of his death. The publication was overseen by Andreus Osiander (1498-1552), a Lutheran and Protestant reformer.  He added a Preface, in addition to Copernicus’s own Dedicatory Letter, most likely without Copernicus’s knowledge, in which, knowing the controversy it was likely to unleash, he put in the term ‘hypothesis’ on the title page in order to suggest the book aimed only to help with calculation and mathematics, and was not claiming to be the literal truth. ‘These hypotheses need not be true or even probable’ (Introduction). It is unclear whether he intended for this to be seen as Copernicus’s own view, although many accept that this was his intention. 

The stakes were high, for the opening line is that these hypotheses ‘sets the earth in motion and puts an immovable sun at the center of the universe’ (Hutchins, 1952, 505). Osiander was trying to defuse the controversy that this would bring and was perhaps also trying to save the appearances of the planets for the orthodox view of the Ptolemaic system which Judaism, Islam and Christianity with the power of the Catholic Church, had tied themselves to. 

Copernicus has something more to say about appearances. It had been asserted by Aristotle that the earth must be stationary because, as was clear to everyone, ‘heavy bodies forcibly thrown quite straight upward return to the point from which they started, even if they are thrown to an unlimited distance. From these considerations then it is clear that the earth does not move and does not lie elsewhere than at the center’ (Aristotle, On The Heavens, 296b 22-4). 

Copernicus meets this with an observation, one made before but hugely significant not just at the time, but perhaps more so later with Galileo, Einstein, quantum physics, and in relation to the question of identity, inequality, and the Great Chain of Being. Copernicus says in Revolutions that obviously what we think is motion can be very deceptive. He quotes Aeneas from the Aeneid (III. 72) that ‘We sail out of the harbour, and the land and the cities move away.’ And then Copernicus adds that in exactly the same way it would appear from the earth, which is actually moving, that in fact it is the rest of the universe that is moving, and the earth is at rest. He refutes Aristotle, and anticipates developments yet to come with Galileo and Newton, that things which are thrown up and fall back to the same place may well ‘conform to the same nature as the earth.’[4] We know this now to be the case that objects in the earth’s air borrow and share the motion of the earth and move with it, again creating the illusion that neither are in motion. We will return to this relativity of motion many times, and we will also look at how it plays out philosophically in Kant’s own version of a Copernican Revolution in metaphysics. 

Copernicus also anticipates another development beyond Aristotle. In Book 1, chapter 9 he suggests that ‘since there are many centers, it is not foolhardy to doubt whether the center of gravity of the earth rather than some other is the center of the world.’ This anticipates a universe of many centers, and, by extension, of no centers. This will begin to become a reality in Galileo some 60 years later. 

But the idea that earth moved was not new. It had been argued by Aristarchus in ancient Greece. And in 1440, over 100 years before On The revolutions, Nicolaus Cusanus, or Nicholas of Cusa, wrote De docta ignorantia, or Of Learned Ignorance. In chapters 11 and 12 (Cusanus, 1967) he made a series of remarkable observations. 

The earth, which cannot be the center, cannot be devoid of all motion … (p. 90)

Though the matter appears to us to be otherwise, neither the sun nor the moon nor the earth nor any sphere can by its motion describe a true circle, since none of these are moved about a fixed point. (p. 92).

And on a theme we will return to in another lecture, he says,

In like manner, we surmise that none of the other regions of the stars are empty of inhabitants. (p. 97).

Nevertheless, the Copernican Revolution has been seen as one of the most important moments in the history of cosmology. It redefined the order of the universe, and perhaps even more importantly, it questioned whether we could trust what appears to our own eyes―whether we trust common sense assumptions about what seems to be moving and what seems to be at rest.

The Copernican Revolution threatened many vested interests, not least that of the idea in the monotheistic religions that God had created the earth at the center of the universe for mankind. Alongside the Reformation, this was to have dramatic implications for the authority of the Catholic Church, and eventually for the growth of secularism or life lived without having God as its cause and meaning. We will follow that path later.  But note that Friedrich Engels (1820-1895) who worked with Marx in the development of communism in the mid 19thcentury, wrote in Dialectics of Nature, that ‘What Luther’s burning of the Papal Bull was in the religious field, in the field of natural science was the great work of Copernicus, in which he, although timidly, after thirty-six years’ hesitation and so to say on his deathbed, threw down a challenge to ecclesiastical superstition. From then on natural science was in essence emancipated from religion’ (1883/1974, 126).

Many such comments have been made about the wider cultural significance of the Copernican Revolution and continue to be so today. Here is just one example that sums up what is often said about it, from Johann Wolfgang von Goethe (1749-1832).

‘Of all discoveries and opinions, none may have exerted a greater effect on the human spirit than the doctrine of Copernicus. The world had scarcely become known as round and complete in itself when it was asked to waive the tremendous privilege of being the centre of the universe. Never, perhaps, was a greater demand made on mankind – for by this admission so many things vanished in mist and smoke! What became of our Eden, our world of innocence, piety and poetry; the testimony of the senses; the conviction of a poetic, religious faith? No wonder his contemporaries did not wish to let all this go and offered every possible resistance to a doctrine which in its converts authorized and demanded a freedom of view and greatness of thought so far unknown, indeed not even dreamed of.’ (Copernicus, 2002, xvi)[5]

Or what about this from WB Yeats from his poem The Second Coming (Jan 1919, after WW1)?

Turning and turning in the widening gyre
The falcon cannot hear the falconer;
Things fall apart; the centre cannot hold;
Mere anarchy is loosed upon the world,
The blood-dimmed tide is loosed, and everywhere
The ceremony of innocence is drowned;[6]

This speaks of the idea of uncentring, or decentring. What happens to the Great Chain of Being if the Earth is not the center and its lowest point (or its extreme and furthest point)? And what is the cosmos if the earth is not at the center? And where is God if He is not ordering everything in the universe for human beings?

We can say that the revolution threatened to suggest that mankind was no longer the center of the universe, but merely an occupant of one of many similar satellites. This is an education in the relativity of importance, or in humility, and an education that shifts perspective and understanding on almost everything that had been previously believed. 

De we need to be centered in our lives?

But we can observe two comments that might make us pause here. The first comes from I. Bernard Cohen, who asks that we consider the innate conservatism of the Copernican universe and look ahead instead to another cosmologist, Johan Kepler, as the truly radical figure. Cohen says (Cohen, 1981, 25),   

At the outset we must make it plain that Copernicus (1473-1543) was in many ways more of a conservative than a revolutionary. Many of the ideas he introduced had already existed in the literature, and again and again the fact that he was unable to go beyond the basic principles of Aristotelian physics hampered him. When we talk today about the “Copernican system,” we usually mean a system of the universe quite different from that described in Copernicus’s De revolutionibus orbium coelestium. The reason for this procedure is that we wish to honor Copernicus for his innovations, and do so at the expense of literal accuracy by referring to the sun-centered system of the post-Copernican era as “Copernican.” It should more properly be called “Keplerian” or at least ‘”Keplero-Copernican.”

The second caution is now becoming quite well known and fits well in the current narrative of decolonizing the western curriculum of suppressed voices from its history. Jim al-Khalili (2011) notes that there is strong evidence that Copernicus in fact learned much from a 13th century Persian scientist called Nasir al-Din al-Tusi (1201-1274) and his Commentary on the Almagest (1274). The Tusi-couple (concerning the rotation of circles within circles) replaced Ptolemy’s equant, and Copernicus’s diagrams in Revolutions are extremely similar to those of al-Tusi. But what makes some accuse Copernicus here is that he seems to have copied the same lettering in his diagram that al-Tusi had in his. Al-Khalili notes that this does not undermine Copernicus’s reputation for there is no precedent in Arabic astronomy prior to Copernicus for a heliocentric universe replacing a geocentric one.  

But we are going to leave these controversies and try to pick up again on our own question of the origin of inequality in the Great Chain of Being. How does the Copernican Revolution appear when related to this question? Lovejoy has an interesting take on this, drawing on the idea of emanation.

Copernican Revolution and Great Chain of Being

Lovejoy argues that it was not the Copernican Revolution that changed the idea of physical science in the world or the idea of relative size. He argues that relativity of size and magnitude can be found in Ptolemy who said that the earth is a mere dot compared to the size of the heavens, and the Jewish philosopher Moses Maimonides (1138-1204) in his book The Guide of the Perplexed, had noted that ‘if the earth is no bigger than a point relatively to the sphere of the fixed stars, what must be the ratio of the human species to the created universe as a whole? And how then can any of us think that these things exist for his sake, and that they are meant to serve his uses?’ (Lovejoy, 1964, 100).[7]

Here is a retrieval of the kind of education in relativity that the Great Chain of Being had always possessed on its ladder from the greatest, largest and most important, to the least, smallest and most insignificant. But Lovejoy says what held this relativism in place was that the ancient and medieval universe had been fenced in or limited. It was pictured as having a limit, something like a walled city. It was a universe, as C S Lewis said, for the medieval mind, having a place for everything and everything in its place. War had rules, love had codes, thoughts had systems, and the universe had order; ‘the organization of their theology, science, and history [was brought] into a single, complex, harmonious mental Model of the Universe’ (Lewis, 1964, 11).

Lovejoy then offers a different interpretation than that which defines most of the responses to the Copernican Revolution. He notes that we are told that man occupied a central place in the universe from which he was expelled or evicted by the heliocentric model. But says Lovejoy the geocentric model was never this at all, rather the opposite. ‘The center of the world was not a position of honor; it was the place farthest removed from the Empyrean, the bottom of creation, to which its dregs and baser elements sank … And the whole sublunary region was, of course, incomparably inferior to the resplendent and incorruptible heavens above the moon’ (Lovejoy, 1964, 101-2). 

Lovejoy is saying that in the Great Chain of Being mankind was never in an honorable position, and therefore it is wrong to argue that the Copernican Revolution moved the earth from a favored position to a less exclusive one. This does undermine somewhat the common observations that the Copernican Revolution undermined mankind’s privileged position in the universe and reduced the status of the earth to a mere satellite. He rather dryly observes that if there was a sense of self-importance of mankind on earth, it was that it contained the only rational life in the universe, a population whose destiny had yet to be settled. As such, their affairs were deemed to be of such to the Deity that ‘a single natural folly of an unsophisticated pair in Mesopotamia could, by its consequences, constrain one of the persons of the Godhead to take on human flesh and live and die upon this globe for man’s salvation’ (Lovejoy, 1964, 103).[8] At best, the human race was never better (or worse) than the middle link in the Great Chain of Being between wholly unspiritual creatures and purely spiritual gods.

As we have seen, the Copernican model of the universe did not reform the idea of the concentric spheres. Indeed, to be moved out of the lowest part of the cosmos, its center, might be seen as something of a promotion for the earth. But, if the Aristotelian physics of an immovable Earth at its center is now denied, so is its status in religion as the lowest place, and with it the distinction between the sublunary and the immortal heavens. The Great Chain of Being needed the scale of highest to lowest, and without a center, that is beginning to dissolve.

As the earth was now beginning to be defined as similar to other satellites, so the Great Chain of Being took on a whole new lease of life. It could no longer be assumed that life and death only existed on earth as the single project of the creator. Tycho Brahe’s (1546-1601) discovery of the (super) Nova in Cassiopeia in 1572 suggested new worlds as yet unthought and unknown. And his work on the comet of 1577 showed that it must have passed through the supposed crystalline spheres which was thought to be impossible. Put these two together and you have the end of the spheres, and the end of its limited cosmos. Can the Great Chain of Being survive the destruction of the bounded universe of the spheres? Will hierarchy and plenitude collapse without it, or will they somehow find ways of renewing themselves?

One serious implication for the ancient comic model, as we just mentioned, was that in an unbounded universe with many stars, perhaps similar planets to Earth existed in the universe. Perhaps there was life on planets as yet undiscovered. Perhaps, then, it was not so much the heliocentric theory of the cosmos that had most impact on the future, but rather the associated changes that accompanied it, especially the idea of motion being relative to the observer, and that there be no one center to the universe at all, no central point from which the truth of all things could be judged. Lovejoy notes 5 such revolutionary implications

  • That other planets of his solar system might have rational beings on them
  • That the universe was not bounded by the fixed stars
  • That stars might be suns with planetary systems of their own
  • That there might be life on other planets of these other suns
  • That the universe might have infinite space

In the face of these, the uniqueness of the earth could no longer be asserted as it had been in the medieval model. The incarnation of God as Jesus and his redemption and ascension seemed to imply a single inhabited world. We can take as our example here a work by Thomas Paine (1737-1809), known for his pamphlets during the American Revolution (culminating in the Declaration of Independence 1776), and for his Rights of Man (1791). In The Age of Reason (1794, 1795, & 1807) he said, ‘From the time I was capable of conceiving an idea, and acting upon it by reflection, I either doubted the truth of the Christian system or thought it to be a strange affair (Paine, 1807, 45). He continued,

After I had made myself master of the use of the globes, and of the orrery, and conceived an idea of the infinity of space, and of the eternal divisibility of matter, and obtained, at least, a general knowledge of what was called natural philosophy, I began to compare, or, as I have before said, to confront, the internal evidence those things afford with the christian system of faith. Though it is not a direct article of the christian system that this world that we inhabit is the whole of the habitable creation, yet it is so worked up therewith, from what is called the Mosaic account of the creation, the story of Eve and the apple, and the counterpart of that story, the death of the Son of God, that to believe otherwise, that is, to believe that God created a plurality of worlds, at least as numerous as what we call stars, renders the christian system of faith at once little and ridiculous; and scatters it in the mind like feathers in the air. (Paine, 1807, 46)[9]

One danger was that an infinite universe with no center had no rational plan, perhaps no system at all. We will see how science responded to this in the next lectures. But the imagination was caught by the idea of life on other planets. This was not a completely new idea. Democritus and the Epicureans and both suggested an infinity of worlds thesis. Democritus, famous for his laughing at the follies of men, is reported by Hyppolitus to have believed in an infinite number of worlds, and Epicurus believed the infinity of atoms meant the infinite possibility of kosmoi or an infinite number of worlds. 

But now the logic of the Great Chain of Being played a key role. Remember that the principles of the Great Chain of Being were plenitude and continuity; that God or the Good was just and would not refuse existence to anything that was possible of existing. It would therefore be unjust not to give life on planets where life was possible. Remember too, Cusanus. In On Learned Ignorance (1440) he wrote of the likelihood of inhabitants on other planets. He uses the two principles of the Great Chain of Being to speculate on life on other planets: plenitude because God would not hold back from allowing everything to exist that can exist; and continuity because there must be the whole range of possible life, from the highest to the lowest, with no gaps.

Perhaps most famous person in this regard is Giordano Bruni (1548-1600). Lovejoy says here, it is Bruni ‘who must be regarded as the principal representative of the doctrine of the decentralized, infinite, and infinitely populous universe’ (1964, 116). He was a supporter of Copernicus, but his conclusions were based solely on the logic of plenitude taken from the Timaeus. In this sense he is both ancient and modern. In 1586 he argued that ‘an infinity of beings and of worlds must exist, in all possible modes’ (Lovejoy, 1964, 117). Lovejoy adds that for Bruni ‘Of the endlessly numerous worlds thus demonstrated to exist, some … must even be more magnificent than ours, with inhabitants superior to the terrestrial race’ (1964, 118). Bruni’s argument conforms to the Great Chain of Being and its principles of plenitude and continuity. For example, Lovejoy quotes him from his book On Innumerable Things, as complying with the Chain in terms of both principles. 

‘That is perfect which consists of many parts, disposed in a fixed sequence and closely joined together.” It is therefore “not permissible to carp at the vast edifice of the mighty Architect because there in nature some things that are not best, or because monsters are to be found in more than one species. For whatever is small, trivial or mean serves to complete the splendor of the whole.’ (1964, 119)

Note that in 1593 Bruni was sent to Rome for a trial lasting seven years, charged with among other things heresy against established theology and dogma, and he was eventually declared a heretic in 1600, and burned at the stake on Ash Wednesday, 1600, in a square in Rome. His books were prohibited. You might be interested to know that a crater on the dark side of the moon is named after him.

Final thoughts

I hope you can see now that hierarchy here is being released from its attachment to emanation and is being extended across an infinite universe. Our enquiry into the origin of inequality is now taking us from inequality on earth to inequality in an expanding universe. Even in current sci-fi hierarchy is rehearsed in terms of higher and lower beings. 

Let us now look ahead to the next stage of our enquiry. The Great Chain of Being is faced with a problem. Without a center, the idea of emanation with its reproduction of hierarchy starts to unravel. Acentrism, or the lack of a center in the cosmos, opens up the possibility that there is no guiding principle at all. With a God one could still hold to plenitude and continuity in the idea of infinite worlds. But the attachment of God to emanation left God vulnerable in the new universe. How did He work as a principle if not through emanation? What kind of new idea would replace emanation? And what would its implications be for the idea of hierarchy and inequality?

The answer, as we will see in our next lectures, was law and mechanism.


Cohen, I.B. (1981) The Birth of a New Physics, New York, Norton.

Copernicus, N. (2002) On the Revolutions of Heavenly Spheres, edited by Stephen Hawking, Philadelphia, Running Press. 

Cusanus. N. (1967) On Learned Ignorance, Book II, edited by Paul Wilpert, Minneapolis, Arthur j Banning Press. 

Engels, F. (1883/1974) Dialectics of Nature, Progress Publishers; https://www.marxists.org/archive/marx/works/1883/don/ch07a.htm

Hutchins, R.M. (1952) Great Books of the Western World, 16. Ptolemy, Copernicus, Kepler, Chicago, Encyclopaedia Britannica, Inc.

Al-Khalili, J. (2011) The House of Wisdom, New York, Penguin Press.

Lewis, C.S. (1964) The Discarded Image, Cambridge, Cambridge University Press.

Lovejoy, A. (1964) The Great Chain of Being, Massachusetts, Harvard University Press. 

Paine, T. (1807) The Age of Reason, Feedbooks, http://klymkowskylab.colorado.edu/Readings/Thomas%20Paine%20-%20The%20Age%20of%20Reason.pdf

[1] For more on this, see Pierre Duhem. In his book To Save The Phenomena, (1969) Duhem argues that Plato said that by hypothesizing what uniform and ordered motion is it is possible to save the phenomena relating to planetary motion or to save the observable world from disobeying the theory. 

[2] See Cohen, 1981, 26.

[3] in order to overcome the inelegance of Ptolemy’s idea of the equant or equalizing point.

[4] On The Revolutions, Book 1, chapter 8.

[5] Originally from Goethe, Johann Wolfgang von, Geschichte der Farbenlehre, “Zwischenbetrachtung”, in Goethes Werke,Weimarer Ausgabe (Weimar: 1893) vol. II.3, 213.

[6] William Butler Yeats (13 June 1865 – 28 January 1939). The whole poem:

The Second Coming

    Turning and turning in the widening gyre

    The falcon cannot hear the falconer;

    Things fall apart; the centre cannot hold;

    Mere anarchy is loosed upon the world,

    The blood-dimmed tide is loosed, and everywhere

    The ceremony of innocence is drowned;

    The best lack all conviction, while the worst

    Are full of passionate intensity.

    Surely some revelation is at hand;

    Surely the Second Coming is at hand.

    The Second Coming! Hardly are those words out

    When a vast image out of Spiritus Mundi

    Troubles my sight: somewhere in sands of the desert

    A shape with lion body and the head of a man,

    A gaze blank and pitiless as the sun,

    Is moving its slow thighs, while all about it

    Reel shadows of the indignant desert birds.

    The darkness drops again; but now I know

    That twenty centuries of stony sleep

    Were vexed to nightmare by a rocking Copernican Revolutionadle,

    And what rough beast, its hour come round at last,

    Slouches towards Bethlehem to be born?

[7] From Moses Maimonides, The Guide of the Perplexed, Book III. 14.

[8] The Garden of Eden, from Genesis, might have been in southern Mesopotamia, now Iraq.

[9] The orrery has its name from the person who invented it. It is a machinery of clock-work, representing the universe in miniature: and in which the revolution of the earth round itself and round the sun, the revolution of the moon round the earth, the revolution of the planets round the sun, their relative distances from the sun, as the centre of the whole system, their relative distances from each other, and their different magnitudes, are represented as they really exist in what we call the heavens. 

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