C.S. Lewis "rebuts" size-of-the-universe argument. Can you help me find it?

[Find_Friends]

I’m giving a talk on “The Theologian’s Nightmare” this week for the local Bertrand Russell Set.

Now, a few years back, in a current events discussion group, I was highly praised by the moderator (privately) for showing concern that everyone be given a chance to express dissenting views, including those that were very far from mainstream.

I enjoyed the praise so much that that I fully intend to live up to it.

And so I want to include something unusual as one of the hand-outs for folks to read afterward.

…

It seems that Clive Stapes Lewis, a convert to Christianity and author of popularizing essays wrote at least once in a rebuttal to the type of argument Russell uses. (But I don’t think he referenced Russell by name.)

I do recall that one point he made was that greater size does not necessarily entail greater importance. A man’s legs versus his head, for example.

Lewis was especially concerned with the doctrine of salvation through Incarnation, Crucifixion and Resurrection. He saw an apparent contradiction between the traditional assumption of uniqueness of these events, and the strong possibility of intelligent (and, likely, morally responsible) life elsewhere. But he didn’t think the problem suggested was beyond solution. He asserted that it wasn’t necessary for every sentient race to have “fallen” even assuming that such was an inherent possibility every time. (I’m sure that he once said that the vast interstellar distances perhaps existed to “quarantine” fallen races such as ours from non-fallen ones that might be influenced to fall. I recall that a very old issue of TIME quoted this particular bit of his.) He also brought up the possibility of alternate ways God could provide for particular needs for a route of salvation for other fallen species. This, he felt, could leave our own situation unique.

It’s possible that he also went into the idea of our scenario being repeated elsewhere, but I don’t recall that for sure.

Lewis also appeared rather annoyed at the assumption that the “Ancients” did not have any idea of the relative tininess of our planet. He once surprised a skeptic of religion by showing him a classic text that included a statement that the stars showed themselves to be so distant that they may as well be at infinite distance.

(That may sound unlikely to be a true excerpt, or at least something very strange for classical Natural Philosophers to say but here’s the idea. The moon and planets can have their distances measured, at least roughly, by parallax against the stars. But he stars themselves (which are unlikely to be all at the same distance from us) show absolutely no parallax relative to each other.

Of course, modern astronomers HAVE measured the parallax of relatively nearby stars, using telescopes and the whole of Earth’s orbit as the baseline.)

---

So, can anyone locate the particular essay or essays?

- Jack

[The_Other_Waldo_Pepper]

@Trans Fat Og

So, can anyone locate the particular essay or essays?

I believe it’s “A Chapter Of Red Herrings” from MIRACLES.

[njtt]

@Trans Fat Og

Lewis was especially concerned with the doctrine of salvation through Incarnation, Crucifixion and Resurrection. He saw an apparent contradiction between the traditional assumption of uniqueness of these events, and the strong possibility of intelligent (and, likely, morally responsible) life elsewhere.

Lewis was certainly not the first person to see this issue as a potential theological problem. It was raised in the 17th century by Fontenelle, and, at least implicitly, by earlier Copernican writers such as Bruno and Kepler, who both raised the possibility of intelligent life elsewhere in the universe (in Kepler’s case, on the Moon, in Bruno’s, in other star systems). This was not an issue under the Aristotelian cosmology that prevailed before Copernicus, because there the heavenly bodies were conceived to be of a very type to the Earth, and in no way capable of sustaining life. I must say, it does seem that it would be a bit hard on Jesus if he had to go and get crucified on every inhabited planet in the universe in order to redeem the aliens there. I guess Lewis’ view was that we Earthlings are uniquely evil, the only race in the universe that actually needed to be redeemed. (I once read Out of the Silent Planet [puke], and that certainly seemed to be his view there.)

@Trans Fat Og

Lewis also appeared rather annoyed at the assumption that the “Ancients” did not have any idea of the relative tininess of our planet. He once surprised a skeptic of religion by showing him a classic text that included a statement that the stars showed themselves to be so distant that they may as well be at infinite distance.

I do not know what text that might be, but I would not be surprised if it existed. There was considerable diversity of opinion about such matters in the Ancient world, especially early on, in the presocratic period. However, it was certainly not the consensus view, or the view handed on, mainly by Aristotle and Plato, to Later Antiquity and the Middle Ages.

@Trans Fat Og

That may sound unlikely to be a true excerpt, or at least something very strange for classical Natural Philosophers to say but here’s the idea. The moon and planets can have their distances measured, at least roughly, by parallax against the stars. But he stars themselves (which are unlikely to be all at the same distance from us) show absolutely no parallax relative to each other.

No. Again, although there might possibly have been some Ancient thinker who suggested something like that, the standard view (promulgated by Aristotle, but not invented by him) was that the stars are all at the same distance from the Earth, affixed to a sphere concentric with the Earth, and that rotates around it once per day. On this model, you would not expect parallax effects among the stars, and indeed, in the 16th and 17th centuries the lack of any observable parallax amongst the stars became one of the most telling arguments raised against the Copernican model. (Actually, Copernicus himself still placed the stars on a sphere in his model, but the model predicted parallax motions amongst the stars because he had the Earth moving relative to this sphere, which was now centered upon the Sun. Later Copernicans such as Digges, Bruno and Descartes realized that the sphere was not necessary, and that the stars might be other suns scattered throughout space. However, that only made the parallax problem worse, as, in that case, they would be at different distances, and thus should show even more parallax to a moving Earth.)

Incidentally, I am not at all sure that you are right about the Ancients estimating the distances of the Moon and planets by parallax. I have never heard of that. Their relative distances were inferred from the relative speeds at which they were observed to move against the background of the sphere of the stars, with the faster moving objects being taken to be closer to Earth, and thus in a smaller orbit around it, taking less time to complete. (Aristachus also had another method of estimating the relative distances of the Moon and Sun, but it did not involve parallax, and, although it was mathematically sound, he did not get a good answer out of it, because it was highly sensitive to quite small measurement errors.)

[dangermom]

@Trans Fat Og

Lewis also appeared rather annoyed at the assumption that the “Ancients” did not have any idea of the relative tininess of our planet. He once surprised a skeptic of religion by showing him a classic text that included a statement that the stars showed themselves to be so distant that they may as well be at infinite distance.

What you want for that bit is “The Discarded Image,” a book all about the medieval picture of the universe. It’s one of my favorites!

From chapter 3 (detailing the Somnium Scipionis, a classical text):

Scipio now noticed that the stars were globes which easily outstripped the Earth in size. Indeed the Earth now appeared so small in comparison that the Roman Empire, which was hardly more than a point on that tiny surface, excited his contempt. This passage was constantly in the mind of succeeding writers. The insignificance (by cosmic standards) of the Earth became as much a commonplace to the medieval, as to the modern, thinker; it was part of the moralists’ stock-in-trade, used, as Cicero uses it, to mortify human ambition.

In another spot he quotes sources calling the Earth a mathematical point in the universe with no appreciable magnitude.

From chapter 5, on the medieval idea of the Earth:

Isidore in the sixth century knows that the Sun is larger, and the Moon smaller than the Earth. Maimonides in the twelfth maintains that every star is 90 times as big…As to estimates of distance, we are fortunate in having the testimony of a thoroughly popular work, the South English Legendary:…We are there told that if a man could travel upwards at the rate of “forty mile and yet some del mo” a day, he still would not have reached the Stellatum…in 8000 years.

There are several other examples from various sources–that’s just what I found in a two-minute look through a few pages.

[ITR_champion]

@Trans Fat Og

So, can anyone locate the particular essay or essays?

I’m pretty sure that the one you’re thinking about occurs in the book Miracles. Lewis did also write an essay about the theological implications of life on other planets, which appears in The World’s Last Night and Other Eassys. The ideas he discussed there were also relevant to his science fiction series The Space Trilogy.

@njtt

No. Again, although there might possibly have been some Ancient thinker who suggested something like that, the standard view (promulgated by Aristotle, but not invented by him) was that the stars are all at the same distance from the Earth, affixed to a sphere concentric with the Earth, and that rotates around it once per day. On this model, you would not expect parallax effects among the stars, and indeed, in the 16th and 17th centuries the lack of any observable parallax amongst the stars became one of the most telling arguments raised against the Copernican model. (Actually, Copernicus himself still placed the stars on a sphere in his model, but the model predicted parallax motions amongst the stars because he had the Earth moving relative to this sphere, which was now centered upon the Sun. Later Copernicans such as Digges, Bruno and Descartes realized that the sphere was not necessary, and that the stars might be other suns scattered throughout space. However, that only made the parallax problem worse, as, in that case, they would be at different distances, and thus should show even more parallax to a moving Earth.)

Incidentally, I am not at all sure that you are right about the Ancients estimating the distances of the Moon and planets by parallax. I have never heard of that. Their relative distances were inferred from the relative speeds at which they were observed to move against the background of the sphere of the stars, with the faster moving objects being taken to be closer to Earth, and thus in a smaller orbit around it, taking less time to complete. (Aristachus also had another method of estimating the relative distances of the Moon and Sun, but it did not involve parallax, and, although it was mathematically sound, he did not get a good answer out of it, because it was highly sensitive to quite small measurement errors.)

While Aristotle’s views were certainly influential, it was the Almagest by Ptolemy that was considered the authoritative text on astronomy in Europe during the Middle Ages, and Ptolemy was the one that Lewis refers to in making his argument. The actual figures that Ptolemy had for cosmic distances appear in Planetary Hypotheses and he did say that the distances to the stars are vastly more greater than distances within the solar system, though I’m not sure we know how he derived those distances.

[ITR_champion]

Also,

@Trans Fat Og

I’m giving a talk on “The Theologian’s Nightmare” this week for the local Bertrand Russell Set.

Now, a few years back, in a current events discussion group, I was highly praised by the moderator (privately) for showing concern that everyone be given a chance to express dissenting views, including those that were very far from mainstream.

I enjoyed the praise so much that that I fully intend to live up to it.

And so I want to include something unusual as one of the hand-outs for folks to read afterward.
…
It seems that Clive Stapes Lewis, a convert to Christianity and author of popularizing essays wrote at least once in a rebuttal to the type of argument Russell uses. (But I don’t think he referenced Russell by name.)

I do recall that one point he made was that greater size does not necessarily entail greater importance. A man’s legs versus his head, for example.

If you’re looking for a Christian response to the materialist argument using the huge size of the universe, I have an alternative to suggest. G. K. Chesterton’s book Orthodoxy is a record of his intellectual journey to Christianity, and in chapter 4, The Ethics of Elfland, he mentions some of the claims made of materialism that he found unsatisfactory. Here’s part of the relevant passage:

But modern thought also hit my second human tradition. It went against the fairy feeling about strict limits and conditions. The one thing it loved to talk about was expansion and largeness. Herbert Spencer would have been greatly annoyed if any one had called him an imperialist, and therefore it is highly regrettable that nobody did. But he was an imperialist of the lowest type. He popularized this contemptible notion that the size of the solar system ought to over-awe the spiritual dogma of man. Why should a man surrender his dignity to the solar system any more than to a whale? If mere size proves that man is not the image of God, then a whale may be the image of God; a somewhat formless image; what one might call an impressionist portrait. It is quite futile to argue that man is small compared to the cosmos; for man was always small compared to the nearest tree. But Herbert Spencer, in his headlong imperialism, would insist that we had in some way been conquered and annexed by the astronomical universe. He spoke about men and their ideals exactly as the most insolent Unionist talks about the Irish and their ideals. He turned mankind into a small nationality. And his evil influence can be seen even in the most spirited and honourable of later scientific authors; notably in the early romances of Mr. H. G. Wells. Many moralists have in an exaggerated way represented the earth as wicked. But Mr. Wells and his school made the heavens wicked. We should lift up our eyes to the stars from whence would come our ruin.

But the expansion of which I speak was much more evil than all this. I have remarked that the materialist, like the madman, is in prison; in the prison of one thought. These people seemed to think it singularly inspiring to keep on saying that the prison was very large. The size of this scientific universe gave one no novelty, no relief. The cosmos went on for ever, but not in its wildest constellation could there be anything really interesting; anything, for instance, such as forgiveness or free will. The grandeur or infinity of the secret of its cosmos added nothing to it. It was like telling a prisoner in Reading gaol that he would be glad to hear that the gaol now covered half the county. The warder would have nothing to show the man except more and more long corridors of stone lit by ghastly lights and empty of all that is human. So these expanders of the universe had nothing to show us except more and more infinite corridors of space lit by ghastly suns and empty of all that is divine.

In fairyland there had been a real law; a law that could be broken, for the definition of a law is something that can be broken. But the machinery of this cosmic prison was something that could not be broken; for we ourselves were only a part of its machinery. We were either unable to do things or we were destined to do them. The idea of the mystical condition quite disappeared; one can neither have the firmness of keeping laws nor the fun of breaking them. The largeness of this universe had nothing of that freshness and airy outbreak which we have praised in the universe of the poet. This modern universe is literally an empire; that is, it was vast, but it is not free. One went into larger and larger windowless rooms, rooms big with Babylonian perspective; but one never found the smallest window or a whisper of outer air.

Their infernal parallels seemed to expand with distance; but for me all good things come to a point, swords for instance. So finding the boast of the big cosmos so unsatisfactory to my emotions I began to argue about it a little; and I soon found that the whole attitude was even shallower than could have been expected. According to these people the cosmos was one thing since it had one unbroken rule. Only (they would say) while it is one thing it is also the only thing there is. Why, then, should one worry particularly to call it large? There is nothing to compare it with. It would be just as sensible to call it small. A man may say, “I like this vast cosmos, with its throng of stars and its crowd of varied creatures.” But if it comes to that why should not a man say, “I like this cosy little cosmos, with its decent number of stars and as neat a provision of live stock as I wish to see”? One is as good as the other; they are both mere sentiments. It is mere sentiment to rejoice that the sun is larger than the earth; it is quite as sane a sentiment to rejoice that the sun is no larger than it is. A man chooses to have an emotion about the largeness of the world; why should he not choose to have an emotion about its smallness?

It happened that I had that emotion. When one is fond of anything one addresses it by diminutives, even if it is an elephant or a life-guardsman. The reason is, that anything, however huge, that can be conceived of as complete, can be conceived of as small. If military moustaches did not suggest a sword or tusks a tail, then the object would be vast because it would be immeasurable. But the moment you can imagine a guardsman you can imagine a small guardsman. The moment you really see an elephant you can call it “Tiny.” If you can make a statue of a thing you can make a statuette of it. These people professed that the universe was one coherent thing; but they were not fond of the universe. But I was frightfully fond of the universe and wanted to address it by a diminutive. I often did so; and it never seemed to mind. Actually and in truth I did feel that these dim dogmas of vitality were better expressed by calling the world small than by calling it large. For about infinity there was a sort of carelessness which was the reverse of the fierce and pious care which I felt touching the pricelessness and the peril of life. They showed only a dreary waste; but I felt a sort of sacred thrift. For economy is far more romantic than extravagance. To them stars were an unending income of halfpence; but I felt about the golden sun and the silver moon as a schoolboy feels if he has one sovereign and one shilling.

[Chronos]

Maimonides in the twelfth maintains that every star is 90 times as big

Really? If we take that as meaning 90 times as big in linear dimension (radius or diameter), that’s a remarkably close value. In fact, the Sun (a not atypical star, and certainly the easiest one to study) is 109 times the size of the Earth. I’m now left wondering if there was actually some valid measurement of the size of the Sun in Maimonides’ time. Or, of course, it could have been a lucky guess.

[Diogenes_the_Cynic]

The size of the universe is really not an argument used by non-believers so the whole issue is kind of a strawman, but even so, the best anybody appears to be able to do is an argument from absence. I wouldn’t call it much of a “rebuttal,” just an expansion of the fantasy. “Fallen” races vs “unfallen races?” Give me a break. That doesn’t rebut anything, it’s just ad hoc fabrication. It doesn’t provide evidence for anything, and the whole concept of a “fallen race” is, in itself, irrational and easily eviscerated.

The quoted bit from Chesterton is complete gibberish, by the way.

[dangermom]

@Chronos

Really? If we take that as meaning 90 times as big in linear dimension (radius or diameter), that’s a remarkably close value. In fact, the Sun (a not atypical star, and certainly the easiest one to study) is 109 times the size of the Earth. I’m now left wondering if there was actually some valid measurement of the size of the Sun in Maimonides’ time. Or, of course, it could have been a lucky guess.

The direct quotation is on page 100 of The Great Chain of Being, which is handily available on Google Books. Yay for the Internet!

To OP, the same chapter of that book cites Ptolemy on the whole Earth-as-point thing.

[Lumpy]

@Trans Fat Og

Lewis also appeared rather annoyed at the assumption that the “Ancients” did not have any idea of the relative tininess of our planet. He once surprised a skeptic of religion by showing him a classic text that included a statement that the stars showed themselves to be so distant that they may as well be at infinite distance.

(That may sound unlikely to be a true excerpt, or at least something very strange for classical Natural Philosophers to say but here’s the idea. The moon and planets can have their distances measured, at least roughly, by parallax against the stars. But he stars themselves (which are unlikely to be all at the same distance from us) show absolutely no parallax relative to each other.

Of course, modern astronomers HAVE measured the parallax of relatively nearby stars, using telescopes and the whole of Earth’s orbit as the baseline.)

---

So, can anyone locate the particular essay or essays?

- Jack

In “Religion and Science”, Lewis directs a friend who thinks the medieval concept was of a tiny universe to Ptolemy’s Almagest and quotes Book 1, Chapter 5: “the Earth, in relation to the distance of the fixed stars, has no appreciable size and must be treated as a mathematical point”.

[Steve_MB]

@ITR_champion

Also,

If you’re looking for a Christian response to the materialist argument using the huge size of the universe, I have an alternative to suggest. G. K. Chesterton’s book Orthodoxy is a record of his intellectual journey to Christianity, and in chapter 4, The Ethics of Elfland, he mentions some of the claims made of materialism that he found unsatisfactory. Here’s part of the relevant passage:

The quoted passage doesn’t address anything meaningful. Yes, the physical measurements of the universe don’t have any real philosophical significance in themselves. This is so obvious that to belabor it seems, and is, pointless.

The likelihood that other intelligences exist, which is implied but not conclusively proven by the number of stars in the universe, is a more interesting (and troubling to any belief system that rests on a specific event taking place on the specific planet Earth) question, that is nowhere addressed in the quoted text.

[smiling_bandit]

[quote=“Steve_MB, post:11, topic:545807”]

The quoted passage doesn’t address anything meaningful. Yes, the physical measurements of the universe don’t have any real philosophical significance in themselves. This is so obvious that to belabor it seems, and is, pointless.

[quote]

Sadly, it is not a point which can belabored too much, and if it has lost its impact today, it is because people like Chesterton drove it home repeatedly beforehand. His basic point is that if any emotion like awe of the universe is to have value, then it intrinsically values, not devalues, mankind. And this was not obvious at all to certain intellectual classes of his day.

The likelihood that other intelligences exist, which is implied but not conclusively proven by the number of stars in the universe, is a more interesting (and troubling to any belief system that rests on a specific event taking place on the specific planet Earth) question, that is nowhere addressed in the quoted text.

Yet that was also addressed elsewhere - by simply pointing out the very old religious idea that we might not be all that unique, however special we are, and that whatever uniqueness we possessed might not be all to our benefit or glory.

[bonzer]

It’s somewhat incidental, but Albert van Helden specifically singles out the discussion of astronomical distances in The Discarded Image as historically inadequate in his Measuring the Universe: Cosmic Dimensions from Aristarchus to Halley (Chicago, 1985). His argument is that Lewis was unrepresentatively drawing on too narrow and too early a set of sources, some of which he was citing at secondhand. Van Helden’s broader case is that Ptolemy laid out a series of dimensions and, once filtered through the Arab world, that becomes a rather stable tradition in medieval Europe, a set of numbers familiar to any educated man. Which is perhaps the dull conclusion.
Of course, Ptolemy’s universe was huge enough and the tradition held that the Sun and fixed stars were larger than the Earth, so I’m not really sure that van Helden’s point would have made much difference to Lewis.

(Van Helden’s narrative does still throw up plenty of oddities. For example, it’s Kepler who’s the conspicuous example who shockingly concluded that the fixed stars were smaller than the Earth. Being a Copernican did not necessarily lead to the conclusion that the Sun was just one amongst many.)

[Tom_Tildrum]

Lewis’s Space Trilogy also explores the theological implications of life on other planets. Perelandra posits a world in which Adam and Eve do not Fall, for instance.

[JeffB]

@The_Other_Waldo_Pepper

I believe it’s “A Chapter Of Red Herrings” from MIRACLES.

This is chapter 7 in Miracles. You can find most of it online in Google books – check out pages 83-85.

[twickster]

@Diogenes_the_Cynic

The size of the universe is really not an argument used by non-believers so the whole issue is kind of a strawman, but even so, the best anybody appears to be able to do is an argument from absence. I wouldn’t call it much of a “rebuttal,” just an expansion of the fantasy. “Fallen” races vs “unfallen races?” Give me a break. That doesn’t rebut anything, it’s just ad hoc fabrication. It doesn’t provide evidence for anything, and the whole concept of a “fallen race” is, in itself, irrational and easily eviscerated.

The quoted bit from Chesterton is complete gibberish, by the way.

Dio: the OP was requesting help in finding a particular piece of text, not looking to debate the content of that text. Everyone but you has stayed on topic. If you wish to debate this particular issue, start your own thread in GD – this isn’t the right thread for it.

Thanks,

twickster, Cafe Society moderator

[Diogenes_the_Cynic]

@twickster

Dio. Everyone but you has stayed on topic…

This is not true.

[njtt]

@ITR_champion

While Aristotle’s views were certainly influential, it was the Almagest by Ptolemy that was considered the authoritative text on astronomy in Europe during the Middle Ages, and Ptolemy was the one that Lewis refers to in making his argument. The actual figures that Ptolemy had for cosmic distances appear in Planetary Hypotheses and he did say that the distances to the stars are vastly more greater than distances within the solar system, though I’m not sure we know how he derived those distances.

I am not sure what point you are trying to make here, since Ptolemy followed Aristotle in regard to the point I was discussing: i.e. they both held that the stars are arranged on the inner surface of a sphere centered on the Earth, and are, consequently all at an equal distance from the Earth. So far as I am aware, Aristotle had nothing explicit to say about the actual size of this sphere. Ptolemy might have thought this sphere to be pretty big, but he certainly did not regard the stars as other suns, or, a fortiori, as potential centers of other planetary systems.

Anyway, it is misleading to imply that Ptolemy was considered more authoritative than Aristotle with regard to astronomical issues in the middle ages. They were each regarded as authoritative on different aspects of astronomy. Ptolemy was the main source for mathematical astronomy - i.e, the prediction of future planetary positions (mainly for astrological purposes) based upon measurements of past and current positions, and calculated via the complex mathematical apparatus provided by Ptolemy. Aristotle, however, who has little to say about such mathematical issues, was, in the middle ages, regarded as the principal authority on the physical nature of the heavens. Inasmuch as there were any apparent conflicts between the views of Ptolemy and those of Aristotle (and as I pointed out, they did not conflict on the matter I was talking about) Aristotle’s view was generally treated as the more authoritative. For example, it was difficult to see how Ptolemy’s elaborate mathematical apparatus of eccentric orbits and planetary epicycles could be reconciled with the Aristotelian view that the planets were moved around in their orbits by physically real crystalline spheres, concentric with the Earth. The usual response to this was to understand Ptolemy’s system, and mathematical astronomy in general, as making no claims about the physical realities of the heavens at all, but as simply being a mathematical apparatus, a calculating device, for, as they said “saving the appearances,” i.e., for generating predictions from past observations. This is bound up with the fact that natural philosophers, who looked to Aristotle, and who were closely associated with (often the same people as) the moral philosophers and theologians who dominated the medieval universities, generally carried considerably more academic and intellectual clout than did the mathematicians, who were strongly associated with disreputable, religiously suspect practices like astrology and other forms of numerical divination. (Weird as it may seem to us now, to the medieval mind math was strongly associated with woo-woo.)

Lewis may well be right that the Ancients, or some of them, believed the universe to be quite large, and (so far as I can see) he is right that the size of the universe *per se raises no particular problems for Christianity. There is a canard about that one of the sources of opposition to heliocentrism in the 17th century was a sort of agoraphobia inspired by the implication that the universe might be very much bigger than had traditionally been thought. However, I am aware of no evidence whatsoever that this was the case. There was resistance to heliocentrism, but it was based upon a mixture of good scientific reasons, political and careerist reasons, natural (and proper) intellectual conservativism, and (last and very much least) Biblically based religious concerns.

*The likelihood of intelligent life on other planets does raise a problem, and I find Lewis’ response to it to be glib and unconvincing, but that is another matter.

[Find_Friends]

@njtt

No. Again, although there might possibly have been some Ancient thinker who suggested something like that, the standard view (promulgated by Aristotle, but not invented by him) was that the stars are all at the same distance from the Earth, affixed to a sphere concentric with the Earth, and that rotates around it once per day.

I had wondered about that, since several books I had read in my youth showed a celestial sphere, even in representing the Copernican view.

@njtt

On this model, you would not expect parallax effects among the stars, and indeed, in the 16th and 17th centuries the lack of any observable parallax amongst the stars became one of the most telling arguments raised against the Copernican model. (Actually, Copernicus himself still placed the stars on a sphere in his model, but the model predicted parallax motions amongst the stars because he had the Earth moving relative to this sphere, which was now centered upon the Sun. Later Copernicans such as Digges, Bruno and Descartes realized that the sphere was not necessary, and that the stars might be other suns scattered throughout space. However, that only made the parallax problem worse, as, in that case, they would be at different distances, and thus should show even more parallax to a moving Earth.)

This is something I had never come across, nor had it occurred to me, so thank you.

- Jack