Episode 127 - Letter to Pythocles 02 - The Formation of "Worlds"
Date: 06/25/22
Link: https://www.epicureanfriends.com/thread/2561-episode-one-hundred-twenty-seven-letter-to-pythocles-02-the-formation-of-worlds/
Summary
Section titled “Summary”Don reads sections 89-90 on the formation of “worlds” (cosmoi), with Joshua away; the core question is what Epicurus means by a “world” (cosmos) — the group agrees it corresponds most closely to what we now call a galaxy or possibly a solar system, not merely the Earth, and the key Greek term oranos can mean sky or universe. Section 89 describes a world as a “circumscribed portion” of the infinite — possibly spherical, triangular (as the Pythagoreans imagined), egg-shaped (as Empedocles imagined), or any shape — cut off by a boundary whose dissolution destroys everything within; worlds can form inside other worlds or in the interworld (intermundia), from seeds that rush together and aggregate up to a point of equilibrium before eventually dissolving. Section 90 refutes two competing views: that worlds form merely by atomic whirlings in empty space (insufficient conditions), and Democritus’s view that worlds simply grow until they collide with each other (contradicted by phenomena); the sun, moon, and stars were fashioned within a world from the beginning by aggregation of windy or fiery bodies, not created separately and then “taken in.” Martin connects the aggregation-to-equilibrium process to Lucretius Book 2 (lines 11-12) on matter drawn to matter, explains modern nebulae as dust from supernovae seeding new star formation, and notes that earth still accumulates space dust. Cassius closes with DeWitt’s observation that in the Epicurean cosmos the forces of creation and destruction never totally prevail — the universe as a whole is never destroyed — and Martin corrects the ancient Democritean error that galaxy collisions occur because objects “grow into” each other; modern astronomy shows they collide because of overlapping orbital paths.
Transcript
Section titled “Transcript”Cassius: Welcome to Episode 127 of Lucretius Today. I’m your host Cassius, and today we continue with Epicurus’s Letter to Pythocles with a look at the formation of worlds. Joshua is away today, so let’s join Don reading today’s text.
Don: A world is a circumscribed portion of sky containing heavenly bodies and an earth and all the heavenly phenomena, whose dissolution will cause all within it to fall into confusion. It is a piece cut off from the infinite and ends in a boundary either rare or dense, either revolving or stationary. Its outline may be spherical or three-cornered or any kind of shape, for all such conditions are possible, seeing that no phenomenon is evidence against this in our world, in which it is not possible to perceive an ending. And that such worlds are infinite in number we can be sure, and also that such a world may come into being both inside another world and in an interworld, by which we mean a space between worlds. It will be in a place with much void and not in a large empty space quite void, as some say. This is when seeds of the right kind have rushed in from a single world or interworld, or from several, little by little they make junctions and articulations and cause changes of position to another place as it may happen and produce irrigations of the appropriate matter until the period of completion and stability, which lasts as long as the underlying foundations are capable of receiving addition. For it is not merely necessary for a gathering of atoms to take place, nor indeed for a whirl and nothing more to be set in motion, as is supposed by necessity, in an empty space in which it is possible for a world to come into being, nor can the world go on increasing until it collides with another world, as one of the so-called physical philosophers says. For this is a contradiction of phenomena. Sun and moon and the other stars were not created by themselves and subsequently taken in by the world, but were fashioned in it from the first and gradually grew in size by the aggregations and whirlings of bodies of minute parts, either windy or fiery or both. For this is what our sensation suggests.
Cassius: Thank you, Don. Before we jump into what you just read, it’s worth reminding a new listener where we are. The preceding passage established that we don’t investigate astronomy according to arbitrary principles — we are trying to make sure we have a reasonable basis for living happily, avoiding irrational beliefs and groundless imaginings. As long as we have at least one theory consistent with phenomena, that’s where we need to be. And in fact it becomes a hazard if you attempt to choose a single theory when several are consistent with the evidence.
Now, the first question is: what does Epicurus mean by a “world”?
Don: The word used in the original Greek is oranos, which commonly refers to the sky but can also mean the universe. Bailey translates it as “sky,” Hicks actually translates it as “universe.” So whenever Epicurus starts talking later about there being many worlds, he’s not talking about Saturn and Mars and Earth. He’s talking about whole world systems — each with their own earth and sun and moon and stars. A “world system” is probably a better translation than “world.”
Martin: The obvious analogies are that a world as he describes it fits most closely to what we consider a solar system or a galaxy. But it fits both of them about equally. Most of what we see outside our own galaxy are actually other galaxies, not individual stars.
Don: And I think the thing we have to keep in mind is that the perspective of the ancient Greeks is so different from ours. Even Epicurus is thinking of a geocentric cosmos with shells holding the sun and moon and stars circling the earth. So in some ways it’s the observable universe from our vantage point — every infinite point would be the center of its own observable portion of the universe. His reasoning is logically consistent within the worldview of ancient Greece in a totally material-based perspective, and there are interesting analogies to modern astronomy.
Cassius: And that first clause he includes — “whose dissolution will cause all within it to fall into confusion” — even as he’s describing the nature of a world, he’s bringing back the point that everything that comes together will eventually fall apart. That’s a constant theme. What’s the shape of the world?
Don: He says it can be any shape: spherical, three-cornered, or anything else. And I saw a note in one of my sources that the Pythagoreans conceived of a triangular cosmos and Empedocles said it was egg-shaped. So Epicurus seems to be specifically addressing those theories by saying any shape could work — the important thing is that it is a circumscribed portion of the infinite, not the shape.
Martin: And the infinite has no shape at all — it just goes on without boundary.
Cassius: Let me highlight the very last sentence of section 89: these worlds last “as long as the underlying foundations are capable of receiving additions.” So there’s reference to the duration of a world — a beginning and an end. And Martin, Don made an interesting observation that this process of aggregation to equilibrium seems almost exactly how planets and galaxies form today.
Don: Yes — the idea of seeds rushing in and forming junctions and reaching a period of stability — that’s almost spot-on for how planetary bodies and star systems form. And then he says the sun and moon and stars “were not created by themselves and subsequently taken in by the world, but were fashioned in it from the first and gradually grew in size by the aggregations and whirlings.” That’s very close to how modern astronomy describes star and planet formation within a forming solar system.
Martin: Yes. Lucretius Book 2, lines 11-12 puts it this way in Stallings’s translation: “The atoms that compose each substance are apportioned to it by the rain of blows from every direction being drawn to what’s the same — water adds to water, earth increases earth, and flame forges flame, air air, till Nature, maker of things, brings each to the zenith of its growth… when no more can be added to the vital veins than that which flows already in them and now ebbs and drains.” So water is attracted to water, earth to earth. Epicurus doesn’t have our understanding of atomic forces as attraction — he thinks of it mechanically, atoms with shapes that hook into each other — but the general observation works.
Don: And the idea that there is a limit to how much a body can grow — that even something growing must reach an equilibrium point and then begin to break down — reminds me of ordinary things like masonry walls that can’t be built infinitely tall, or bread rising in the oven. Observations from earth, then projected upward.
Cassius: And Martin, where does he get the idea that worlds eventually dissolve?
Martin: There are two aspects. For stars much larger than our sun, they will eventually explode in a supernova, throwing out matter as dust — which is where nebulae get their material for forming new stars. And then there’s the accumulation in the other direction: Earth is still growing because it accumulates space dust. In fact, I’ve heard the Roman ruins in Cologne sit lower than the current city level partly because of accumulated space dust over two millennia. He probably arrived at the dissolution idea by analogy with things he could observe on earth — earthquakes, floods, volcanoes — which seem to shake the foundations of the world and could, if stronger, break it apart.
Cassius: Now section 90 — the two opposing views he’s refuting. First: it’s not sufficient “for a gathering of atoms to take place nor indeed for a whirl and nothing more to be set in motion in an empty space.” So just atoms spinning around in empty space isn’t enough — the right conditions have to be present. And second — “nor can the world go on increasing until it collides with another world, as one of the so-called physical philosophers says.” That’s evidently Democritus.
Don: Yes, that’s how I read it — Democritus held that things just keep growing until they collide with each other. And Epicurus says this contradicts phenomena — you look up at the sky and you don’t see the sun continuing to grow larger every year.
Martin: In modern astronomy, galaxies do collide — but because of their overlapping orbital paths, not because they grow into each other. So Martin’s correction to Democritus would be exactly right.
Cassius: There’s a larger point worth making that connects all of this. DeWitt has an observation somewhere that in the Epicurean cosmos the forces of creation and destruction are constantly working, and everything changes, but in the big picture the forces of destruction never totally prevail — the universe as a whole is never destroyed. There’s always going to be creation somewhere. That’s an ultimately positive attitude toward the universe, not a nihilistic one.
Don: And that practical point you’re making there is always the one that matters — taking theory and putting it into practice. Everything Epicurus talks about in the end has to have a practical benefit for mankind. The destruction of the universe at some point helps keep things in perspective; but you always go back to the words of the philosopher having to have a practical benefit for the happiness of mankind.
Martin: Nothing to add.
Cassius: One last observation: we haven’t talked about the gods in the intermundia today — and in fact the Letter to Pythocles doesn’t address it specifically. For those looking for that material, the best reference is the Velleius narrative in Cicero’s On the Nature of the Gods, Book 1, and in Lucretius. But in this letter Epicurus is focused on the meteorological and cosmological material — the natural workings of worlds — and the gods simply don’t come up here.
Well, Don, I look forward to having you back next week. Joshua is also returning. And next week we’ll look at the famous passage on the size of the sun, which we’ve been building up enthusiasm about for a while. Thanks everybody, and we’ll see you soon.
Don: All right, thanks. Goodbye.
Martin: Bye.