Roman dodecahedra between Southeast Asia and England, part 5

« previous post | next post »

Spotted on the counter for tea/coffee service at the Residence Inn in Omaha, Nebraska:

They're everywhere.

The top pentagonal face of this one is open, so that the dodecahedonal pot can serve as a receptacle for used tea bags, etc.  I inverted it so that you could see from the label on the bottom that it was produced by a design studio that has global aspirations.

Pure white dodecahedron, no holes in the sides — a perfect, Platonic, polyhedron.

Kind of a cross between a simple, regular polygon and a sphere.

The dodecahedron encompasses the universe and all the heavenly bodies within it.

The zodiacal constellations represented by the 12 faces of the dodecahedron symbolize all the stars and planets and galaxies in the cosmos.

Eminently satisfying — at least to me.

Selected readings

[Thanks to Sean Korsmo for the photograph]


  1. Petagon said,

    June 8, 2024 @ 9:41 am

    Now I suspect the Pentagon Building has an intriguing meaning behind: relating a pentagon to a dodecahedron.
    By doing so, the whole universe is under the control by the United States. Just like a ceremonial robe of an ancient Chinese Emperor, celestial bodies are arranged nicely it to show the connection of the Heaven and the Son of Heaven.

  2. Victor Mair said,

    June 8, 2024 @ 4:46 pm


  3. Terry Hunt said,

    June 8, 2024 @ 5:36 pm

    As an astronomer, I find "The zodiacal constellations represented by the 12 faces of the dodecahedron symbolize all the stars and planets and galaxies in the cosmos" less than wholly satisfying, at least as interpretable in classical Greek thought as argued in previous parts of this series.

    Firstly (and trivially), neither Plato nor any other classical writers had any knowledge whatever of galaxies. Their cosmos comprised the central Earth, several wandering 'planets' and an outer spherical shell of fixed stars. (Comets and meteors were both thought to be meteorological, i.e. atmospheric, phenomena.)

    Secondly, the dodecahedron is not a bad approximation to the celestial sphere, but the 12 zodiacal constellations form only a narrow circular band or belt around the latter. There is simply no direct physical correlation between them and the 12 dodecahedral faces.

    The paths of the naked-eye 'planets' (which for classical writers included the Sun and Moon but not the Earth) are confined to a zone only about 17 degrees wide (about 3 arms-length fist-widths) that passes through the thus-defined zodiacal constellations (and at least one other not usually counted – Ophiucus) though parts of them extend a little further. (Classical writers thought of a constellation as comprising specific stars only, rather than a whole area of sky as we do today; thus many stars and areas of sky were not part of any constellation, zodiacal or not.) The zodiacal constellations vary greatly in extent, deviating a good deal from the idealised 30-degree width of the notional 'astrological signs', which due to the precession of the equinox (which cycles over each 25,800 years) no longer coincide with the actual constellations they were named for as they did some 2000 or so years ago.

    While the Roman hollow and pierced dodecahedra may well have had some symbolic meanings (as solid ones undoubtably did), I have yet to hear a description of any remotely practical method by which they, with their varyingly sized holes and non-standard dimensions overall, could be used to make observations of any kind relevant to astronomy/astrology, or other discipline (and that could not be made much more easily by other methods) as has been claimed. I await one – preferably with diagrams – with interest.

  4. Victor Mair said,

    June 8, 2024 @ 6:38 pm

    The Greeks definitely could see — and name! — the 12 zodiacal constellations, and they surely were aware that there were countless other naked eye planets and even galaxies (the Milky Way and Andromeda) in the heavens, just as we are.

    You don't have to be a professional astronomer to see and contemplate them.

  5. Lucas Christopoulos said,

    June 9, 2024 @ 2:03 am

    @Terry Hunt
    "Firstly (and trivially), neither Plato nor any other classical writers had any knowledge whatever of galaxies. Their cosmos comprised the central Earth, several wandering 'planets' and an outer spherical shell of fixed stars. (Comets and meteors were both thought to be meteorological, i.e. atmospheric, phenomena.)"

    Not really…remember that you are an astronomer because of them…

    Epicurus (Greek: Ἐπίκουρος 341-270 BC), Letter to Heraklitos:

    The universe is infinite; for what is finite has an extremity, and what has an extremity is conceived as bounded by something. Therefore, that which has no end has no limits, and that which has no limits is infinite and without term. Now the universe is infinite in two respects, in relation to the number of bodies it contains and in relation to the size of the void: because if the void were infinite and the number of bodies was not, the bodies would not would have no place where they could settle, and they would wander scattered in the void, because they would encounter nothing to stop them and would receive no repercussions. On the other hand, if the void were finite and the bodies were infinite in number, this infinity of bodies would prevent them from having anywhere to be placed…

    IX. THE WORLDS IN INFINITE NUMBER. There are infinite worlds, whether they resemble this one or not; for the atoms, being infinite, as has been shown, are transported to the greatest distance; and as they are not exhausted by the world that they serve to form, not being all employed either in one or several limited worlds, whether they are similar or not, nothing prevents there from being infinite worlds designed in this way

  6. Lucas Christopoulos said,

    June 9, 2024 @ 4:04 am

    Sorry, Letter to Herodotus, not Heraclitus

  7. Daniel Deutsch said,

    June 9, 2024 @ 8:28 am

    Perhaps of interest:

  8. Terry Hunt said,

    June 9, 2024 @ 11:42 am

    @ Victor Mair. No. I'm sorry, but you are wrong. One or two Classical philosophers may have theorised a boundless cosmos with as-yet-unseen other stars and planets, but the Classical world only knew of the 7 'classical' planets (Sun, Moon, Mercury, Venus, Mars, Jupiter and Saturn – let's not get into the Greek or other names). They had no conception whatever of a galaxy as we understand it: Andromeda was a dim smudge that, if they noticed it (it was first mentioned by a 10th-century Persian, as far as we know), they could not know was made of stars (this was only conjectured in the 18th century and observed in the 19th, using a large telescope). Nor could they resolve the misty irregular band of Milky Way (or the Magellanic clouds, first mentioned by a 9th-century Persian) into stars, and had no idea it was a collection of countless stars, an idea first proposed by yet another Persian in the 11th century, and first observed (telescopically) by Galileo in 1610. (A couple of Ancient Greeks had suggested it was the diffused glow from some bright stars hidden by the shadow of the (fixed) Earth – Aristotle and others disagreed.)

    Of course they could all see, easily, the Zodiacal constellations, and a few dozen others, and see the 7* naked-eye planets moving in unexplained ways through the former over the course of months and years, as all cultures have done for many millennia. They could, and some cultures did, build large structures to help measure these movements more accurately: small objects like the Roman dodecahedra, however, would be of no use (that anyone has explained) in making any relevant observations.

    (*Neptune and the minor planets Ceres and Vesta are occasionally also naked eye objects, but there is no record of anyone seeing them before the modern era. A few exceptionally keen-sighted people can see the four Galilean Moons of Jupiter (whose glare obscures them to the normal eye), but again no-one is known to have done so before the 20th century. There are certainly not " countless other naked eye planets": seven including the Sun and Moon, are all the Ancients ever knew about.)

  9. Rodger C said,

    June 10, 2024 @ 10:30 am

    Terry Hunt, by Neptune did you mean Uranus?

  10. David Marjanović said,

    June 11, 2024 @ 3:06 pm

    I'm going with "yes"; I've read elsewhere that Uranus is, under unusually good conditions, just barely visible with the naked eye, but there's no record of anybody seeing it before it was officially discovered through a telescope. Neptune is not visible with the naked eye to the best of my knowledge, and it is both smaller than Uranus and awfully far away.

RSS feed for comments on this post

Leave a Comment