Two Suns In Early Greek Astronomy
retired school teacher.
It seems that the first sages of Greece knew all secrets of Nature. The Heliocentric system was of no mystery to them [they used it for estimation of distances to heavenly bodies as Aristarchos of Samos did]. The Geocentric system they exploited for observation of the planetary movements under Eudoxian theory of the epi-syclers. And then they knew the third system - for heuristic purposes they dealt with pythagorian world picture that had two Suns [or a double one rather]. The following generation of scholars made hay of three, and so today there is a fine medley on the theme in the available fragments...
What concerns the Sun from very beginning in Greek language there were two words for Sun: Theos and Helios and they were not synonyms. Theos was star like object and scholars never discussed a possible form of it or distance to - for them it was eternal, very remote and almighty, "unmoved mover" in Aristotle. Just other way Helios was treated in their stories. Earth mates with him soon after her own birthday and a difference between Helios and Theos in fine was like that between husband and father. Helios was obliged to stay by her in a distance that was remote from her on 27 diameters only. She had gracious waltz with him around Theos, and a merry-go-round by Helios, and a precious little twirl by herself - these three movements they knew from the time of yoke [and which Eudoxis adopted, too].
All three movements can be depicted without any mythological veil like on our drawing 1 [see above] Her twirl means a rotation around axes going through north-south poles; it gives alteration of days/nights. Merry-go-round is a turning around Helios that makes annual movement, which changes seasons on Earth. It was a discussion on the item about what moves indeed - the whole bowl of Earth or her solid sphere only [a cortex].
The Great Year movement [GY] was a great enigma. First of all, how could they know of it? If observing precession then there can be a demur for it was discovered much later than GY. Secondly, it is too long period to be observed by man. GY can be a pure theoretical inference yet. We know now [according to famous theorem of Goedel about fullness] that Earth, as a 'closed system', can not belong to infinity directly but should have first a 'substantiation' in the larger system. The ancients did not know this theorem but the idea was fitted in their paradigm [I shall show it below]. Further, if our 'closed system' is alive then nearest to it largest one [or fullness] should be substantially the same kind, so having a time and movement that in turn could have had a name GY. They had a various estimations of its period, from very short [600 years] to very long [10,000-13,000 in the round numbers]. However they mostly dealt with only two of three as considerable for Earth. Aristotle hardly mentions the third in his treatises. It seems that this movement brought about the greatest changes only [the catastrophes] and in daily and seasonal life played no any role. Plato tells in Tim. about 'perfect year' to boot but that can be of a secondary nature.
The problem about two Suns had been provoked by next primal question - does the Earth see the stars by herself or while man sleeps at night do the stars twinkle in the sky? In ancient time they held the view on that Earth is a living creature and so she should see [though in TIM. Plato said that she had no need in any organ being self-sufficient]. Her vision was specific and resembled more a mirror than eye [by the way Eudoxus had a treatise of the title]. It seems they distinguished the real stars that were very remote from Earth from their presentment in earthly mirror. These latest they perceived as ignited clouds. Every was wheelshaped in form with a rim filled with a mist, and a flame escaping through an opening, viz. they were the sources of light of direct action as the Sun but very weak in power. They shimmed because that mist around a ray was fickle [see dr.2]. Of course, here mist, flame, clouds were earthly essence of the sky, i.e. the mirror was not a glassy thing but some mixture of 'soft air with little fire' and addition of crystalline water with the polished wee particles of alkali metals, mainly sodium.
There were two Moons, too - real one or Luna and her image in the mirror that had three names: Diana was a full Moon, Selena was a Crescent and Hecata was a new Moon [always invisible]. The real Moon was like Earth in nature and maybe with the dwellers even, but Diana and Selena was phenomena, i.e. a result of reflection to Earth a light of Helios by a real Moon that was nearby him. Hence portrait of Moon is a result of indirect action of light.
Sun being so strong in power as a source of light can not have an effigy but more complex construction. Guthrie [in his commentary to fragment A19 from Philolaus] writes that way 'the use of "diethunta" as well as "esoptroeidos" may seem to imply that the Sun is simultaneously being described as a kind of burning glass through which rays pass and also as a reflecting mirror' [v.1 p284]. Here it is interesting to cite Burnet's next words, too: 'the light of the fiery hemisphere is reflected by Earth on to the fiery hemisphere itself in one concentrated flash' [s. K-R, p334]. Both remarks are keen but Apollonius of Perga proved in his time yet that hemisphere could not make a burning focus, it did parabola only.
Now I must turn to the arrangement of our world because it's impossible to get two Suns on modern scheme of the Earth. They saw her as a cosmos [an order], and a solid surface [a cortex, a safety asylum to all] was located in the middle but in a center there was Central Fire [CF or hearth of the world]. From outside cosmos was surrounded with Peripheral Fire [PF or sheen] and so from top to bottom it was warmed with fire [that had many forms]. Further, between CF and cortex there was the greatest chasm of 'tartaros'; again between cortex and PF there was the vastest pasture of heaven. These both volumes were filled with the same stuff [four elements - fire, air, water, earth] but in a different state of matter: underneath they were compressed and above rarefied [dr.3]. Hence, they were these two opposites out of which any existence should consist according to ancient opinion [hot/cold, dry/wet, active/passive]. Some common tension united them all, being based on the notions of unit and limit. Since it was hard to explain the very first notions physically they would turn to mathematics [that way Porphirios says in Vita Pythagoras], and so we must follow them here [but shortly].
The main apprehensive idea [or paradigm] of modern science differs much from that of ancient. Today it is 'numerical line' [NL] and then it was decad [dr.4]. The most glaring differences are next - decad has no zero in a center but unit [number one] and it has terminal number as limit [ten] after which unit increases at a particular jump and then does it regularly after ten new numbers [at 100 - 1000 etc]. That way some infinity [continuous] may be measured by other [discrete]. For the notion of NL next argument is true: however big number L can be L+1 will be bigger as line has no terminal; so we know now about absence of the biggest number. On the contrary decad forbids to think that way as L can happen to be so big that addition of the initial unit never can be discerned by anybody [there was Zeno's axiom on the item, see Arist. Metaph. 1001b7]. Hence, the notion of limit was intrinsic to decad, and now it is the special theorem of Goedel [of fulness] for correcting NL idea.
The most important consequence that ensues from decad is an inference about two limits, convergent and divergent. Let me demonstrate them both here. When numbers in decad are running to periphery they have at least one parameter equal among them [to belong to the same set], and other that changes, and so the whole movement strives for limit. Convergent one can be demonstrated that way: in decad unit is a circle and numbers [2-9] are rings [ten is either ring in a first decad or circle in a second]. Being equal in area they will dwindle in width to periphery and form a sort of callousness at ten [or bark]. On the contrary, under enlargement above cortex [for elements here not restricted from the top] they had to have counter movement to be not dispersed into outer space. That movement pull them back being based on the close propinquity to one another ['like knows like']. That way a state of constant tension [or 'polintonos'] arose, and so a modern idea of 'gravitation' was substituted with ancient idea of 'limitation' that decad [as paradigm] imposed on.
I show them on this schooling model of four elements. Those underneath were in a state of contraction and above enlargement. In both cases they were in equivalence. Of course, in nature there were more elements than four and nearest was pneuma, or fire-in-possibility [as Arist. calls it in Meteor.] It pieced all spheres from center to periphery and congregated under a roof of the world. Among modern elements it resembles much alkali metal and in particularly sodium. It had double entity - dry and wet; it played the biggest role in the animation of world. Pneuma was not a primal essence like the first four elements but it have a secondary nature. The main function of it was to be a self-moving force in the bodies and so unite them all. Since light of the Theos was alien to Earth it can't be used by her directly and so pneuma serves as mediator, too. Now we must descend into the greatest chasm of Tartaros to see how it works. It was an awful spectacle there [even Gods feared to peep in as Hesiod says in Theog.] There was a hearth of Hestia there with a pot boiling on it. Here Goddess cooked these four elements and pushed them above to cortex There was the greatest chaos with thunderstorms and din and blasts and so on. Plato suggested putting order on chaos for better understanding by supposition of two tremendous torrents [Kokit and Phlegeton] swept one through another. As their rush is sinuous [or better to say like sinusoid] so above cortex we have alteration of high/low pressure in the atmosphere. Earth breathes as her bosom moves because chaos works deep in her entrails. And this breath is pneuma as a limit which four elements produce in their flight upwards, viz. Pneuma is a transformation of everyone of them into the most active essence [after segregation from the passive ones that abides by cortex]. Only recognition of pneuma as limit can explain the very phenomenon of two Suns.
The Theos we know, as the Sol [sole] was invisible because Helios would screen him constantly having been located so near to Earth and in front of him. Theos was the common luminary to all known planets [to people there were five, to scholar maybe 180]. Some of this planets [as Venus] perhaps had their own helios [because phases on her surfaces]. These planets were alive and Theos was their Lord, First Mover, Unmoved Mover, Demiurges, Mind and so on [to dead ones He was a scavenger]. The space that surrounds Theos was a generating room [or nursery]. Plato denied independent subsistence of space, and Myth gave it female names [Theia, Providence or Nurse].
This main Star in our Universe was very distant and our cosmos made travel around it for Great Year. It was immensely big in sizes and abundant in stuff and virtually He occupied the other plane than Earth [I've marked it with dotted line]. Hence Theos could not go into direct action with Earth but CF only. It seems there should be third agent [or two] for liaison, and here's dr.5-6 for explanation.
Helios had inlet and outlet which I denominated as S2 and S3, so S2+S3=Helios.
Let it be proposed here that solar radiation from Theos came to Earth in a form of spiral and according to the rule of Max Planck [i.e. 'radiation is incased in portions'] and stuck in CF and only the lesser part of it [ether] pierced through and went on and out. But visible light stays outside, making a deep gouge in a sheen of Earth in a form of parabola. More strong part of irradiation breaks through bottom and goes down to surface but visible light mostly suffers rebuff and gets reflection back again:-this way parabola creates focus, or burning concentration of rays. This is the inlet, i.e. that side of Helios, which looks to Theos and deals with 'being' as main essence. Focus generates a pencil of rays in a form of whirling shaft [or beam], or spindle of necessity [as they called it]. The rotation of that spindle is a true cause for separation of elements out of irregular masses of earthly stuff. Later the Poles of Earth dropped out of the shaft and now there is an angel between them [so daily revolution and generating rotation don't coincide]. S2 is a mock sun - maybe it's impossible to discern Him physically in space [save as brightest shine of the spot].
S3 was a bon-fire, and pneuma was a fuel for it. Evaporation lifted it above and after consumption it fell down in a form of porous small fraction which sometimes shot like sparks. Anaxagoras said that the sky was full of them [the name for them was aerolith but now they are meteorites]. A whole consumption above depended on a violent and contrary movement of Kokit and Periphlegeton in the Earth's entrails [or in Tartaros].
CF was like a nuclear core in our world and PF [with S2 and S3] was as electronic cloth around it [with solid cortex between], so on a whole cosmos was like atom in the solar Universe. S3 was an outlet in the atom through which the bunch of burning rays rushed down to surface, and so it was sensual subject to all breathers on Earth. Yet Helios was not a focus of heat only, but through S2 and S3 the other emanation of S went on and part of it was 'intellectual'. It had but a little interaction with earthly material and then they would call it Mind. It seems true to conclude here that out of three [S + S2 + S3] the first was a 'parent' and next two were his attendants with special services. I can depict S2 and S3 as that temple of Janus with two doors through which roman army marched to battle [and after it]. This temple was a symbol for initial and crucial deeds.
Now Parabola was not a solid thing and so did not reflect a light in full back making focus [as it had to be]. It was translucent and made a lens rather than focus. That lens was flat as a leaf and ridded on air. It moved up/down in aphelion-perihelion cycle [they would call that movement 'tropoi'or turns and estimated distances in 27-29 earthly diameters]. In some sense that movement was the first engine [vertical one] that got energy from Theos and by spindle as a gear transmitted it into Tartaros where it was transformed into horizontal flight of those two floods [Kokit+Periphlegeton] there. That way three-dimensional world had got his frame and existence...
To a conclusion. In the last sentence of Timeaus Plato tells about two Gods: - one intellegible and unseen and other sensual and visible but it would have been much better if he just drew them, viz. Theos as the maker of this cosmos; Helios as the main engine in it; Spindle of Necessity as a moving force and at last the great chasm of Tartaros where like in a kitchen the pot was boiling that nourished our life. In antiquity they did drew schemes needed since every sage was a big devotee of geometry. One of them said that without knowledge of geometry there nothing to do in philosophy!
Now a reader can see on our dr.7 how Philolaic system might had been transformed into Ptolemeic and then to Copernican one. Ptolemy made Sun a single [Sol] and Theos he converted into a fiery heaven [Empireum]. Hence he preserved incommensurability though the Sun had become a fiery body [out of mock Sun]. Copernicus removed Sun to a realm of stars and made them merely the fiery bodies. Their relations with Earth had become rational [more/less]. Now nobody of them can pretend to be the Lord-Creator [being without any sense]. Plato's view on the topic was next: 'We both, proving existence of Gods, tell the same: Sun, Moon, Stars, Earth are Gods, something divine' [Laws X, 886d].
Hence, after Copernicus Lord-Creator has become human-like, and to the mystery of Demiurge was put the end. Now the illustrious phrase of Democritus [that God is a Mind in a spherical fire] sounds but very uncouth indeed!
1. Cornford F.M., Plato's Cosmology, L. 1937.
2. Kirk G.S., Raven J.E., The Presocratic Philosophers, Cmbr. 1957.
3. Guthrie W.K.C., A History of Greek Philosophy v1, Cmbr. 1962.