Did the Romans know the Earth was round??

[Retrospectator]

According to the "Wikipedia," it appears that the Earth was 'generally acknowledged' as being spherical in shape by the time of Pliny The Elder:

http://en.wikipedia.org/wiki/Flat_Earth

I suspect that Pliny here mentions this as a fact somewhere in his Natural History although I can't give a reference at the moment. I also suspect that he here comments on the extent to which it was 'common knowledge' in the Roman world at that time. Tacitus was in touch with Pliny The Younger I believe, and so may have had reasonable access to Pliny The Elder's work. If the above is correct, then Tacitus was evidently inclined towards his own belief.

[Heliodromus]

Tacitus's description is interesting not only for the description of what sounds like a flat earth, but also for what happens to the sun at night, and the two are obviously logically connected. If the earth is known to be round then the motion of the sun - rising in the east, and setting in the west - is easily explained by it passing behind/around the earth (whether one understands this due to motion of the sun or rotation of the earth). Tacitus's view is obviously rather different - he apparently doesn't see the setting sun sinking below the level of the earth, since he ascribes the dark sky at night to shadows thrown on the sky by mountains that block the sun (and absent at the flat extremities of the earth), rather than the sun moving behind the earth and therefore blocked by it.

Tacitus wrote "Agricola" c. 98AD, but we can see the same belief still present in another educated man - an anonymous rhetor who delivered a panegyric to Constantine at Trier in 310AD. Speaking of Britain, the place of Constantine's acclamation as Augustus (but subsequently demoted to Caesar by Galerius), the rhetor says:

"... There are no monstrous beasts in the forests, or deadly snakes on the ground, but on the contrary an immense profusion of tame animals with udders of milk, or loaded with fleeces. The main reason why life is loved is that the days are very long and no nights are without a little light, as the level extremity of those shores does not throw up shadows, and a view of the sky and it's stars overcomes the limit of the night, so that whereas the sun itself seems to us [in the mediterranean] to set, over there it appears to pass along the horizon. Gods above, why is it that always from some furthermost boundary of the earth come new manifestations of the gods to be venerated by the whole world? Thus did Mercury from the river Nile, whose source is not known, and thus did Bacchus from India, practically the place where the sun rises, present themselves to the world as mortals. Assuredly, places neighboring the sky are more sacrosanct than areas in the middle of the lands, and from there, closer to the gods, where the earth ends, was sent our emperor."

Ben

[Retrospectator]

Tacitus wrote "Agricola" c. 98AD, but we can see the same belief still present in another educated man - an anonymous rhetor who delivered a panegyric to Constantine at Trier in 310AD. Speaking of Britain, the place of Constantine's acclamation as Augustus (but subsequently demoted to Caesar by Galerius), the rhetor says:

"... There are no monstrous beasts in the forests, or deadly snakes on the ground, but on the contrary an immense profusion of tame animals with udders of milk, or loaded with fleeces. The main reason why life is loved is that the days are very long and no nights are without a little light, as the level extremity of those shores does not throw up shadows, and a view of the sky and it's stars overcomes the limit of the night, so that whereas the sun itself seems to us [in the mediterranean] to set, over there it appears to pass along the horizon. Gods above, why is it that always from some furthermost boundary of the earth come new manifestations of the gods to be venerated by the whole world? Thus did Mercury from the river Nile, whose source is not known, and thus did Bacchus from India, practically the place where the sun rises, present themselves to the world as mortals. Assuredly, places neighboring the sky are more sacrosanct than areas in the middle of the lands, and from there, closer to the gods, where the earth ends, was sent our emperor."

Ben

Well done for finding that quote! Do you think that this belief (shared by Tacitus) could still have been held by some at this later time, or could it be possible that the rhetor had simply used Tacitus' Agricola as a source with which to add colour to his poetic praise of Constantine? Interesting.

[Bill Perry]

Or... could it be Tacitus was doing all his historical writing from his couch based on stories written or given by word of mouth to him?

The problem with many ancient Roman "historians" is that they did not actually try to find out what these lands were like themselves (and had no photo/movie/sound to judge on their own) but wrote about what others told them it was like - and more than likely these were people in their own class who also did not travel to these places. And the ones that did usually embelleshed the tales to make it sound much more interesting.

Reading these guys more often than not reminds me more like I'm reading articles in the "Enquirer" or "Sun" type of tabloids where aliens have landed and other fantastic events. Though Julius Caesar's writings were largely for his own purposes in getting what he wanted out of Rome - they at least seemed accurate. I sure wish more reports from the legions in the field survived as I think these would have been much more educational. Especially from the legions of Hadrian and Trajan - now that would give an idea of the economies and peoples of the times.

Unfortunately all we are left with is the wonder and glory of the print tabloids of the time - which we are forced to call historians - because the upper classes considered them as such. Not to put down that they did not have kernels of valuable historical fact - especially when talking about their own class and the power struggles within it - but its usually buried in so much fluff and politics of the time that its hard to tell what it was really like in the world of his times.  And almost totally untrustworthy when they record political enemies - though occasionally some things pan out in the archeological record.

In the end, there are "the world is flat" clubs today. There are tabloids today.  There are current event reports so fogged in politics you'd be hard pressed to figure out what was really going on until 10-20 years have passed. In conclusion, Tacitus believing the world is flat while the travelers, and laymen of the time understood differently - is almost as shocking as... as.... people always believing the end times - are in their time As bad as news makes the world to be - its never been better in the history of man - not to say we should not point out injustices - decry attrocities - but the last people I'd believe to see their own times objectively - are the people in those times Me included.

[Heliodromus]

Do you think that this belief (shared by Tacitus) could still have been held by some at this later time, or could it be possible that the rhetor had simply used Tacitus' Agricola as a source with which to add colour to his poetic praise of Constantine?

The quote does seem directly inspired by Agricola or a common source, although it also goes a bit further in spelling out the belief behind it in that last sentence "places neighboring the sky are more sacrosanct than areas in the middle of the lands, and from there, closer to the gods, where the earth ends".

The comparison of Constantine to the gods from far flung corners (or rather edges!) of the world is obviously panegyrical hyperbolae, but I'd have to guess that the world view it is built on must have been assumed as a common reference with it's intended audience.

I have to imagine that belief in a round earth would have been rather esoteric knowledge held by a minority. It's easy for us post-Copernicus, post-Magellan, post-Newton, in the age of satellite imagery & space travel, to believe that the earth is round, and to understand that those "upside down" people on the other face of the world to ourselves are really right-way up in their own perspective, but this really is very counter-intuitive!

I'd have to imagine that to the man in the street the fact that earth was flat was self-evident, and the notion of a round earth, even if they had heard of it, might be considered as some philosophical absurdity rather than a hard reality (that only makes sense once many advances in knowledege had been made).

Ben

[David Atherton]

For what it's worth, here is Pomponius Mela's take on the shape of the earth in his 'Description of the world' written in the mid 1st century:

Whatever all this is, therefore, on which we have bestowed the name of world and sky, it is a single unity and embraces itself and all things with a single ambit. It differs in its parts. Where the sun rises is designated formally as east or sunrise; where it sinks, as west or sunset; where it begins its descent, south; in the opposite direction, north. In the middle of this unity the uplifted earth is encircled on all sides by the sea. In the same way, the earth is also divided from east to wast into two halves, which they term hemispheres, and its differentiated by five horizontal zones. Heat makes the middle zone unlivable, and cold does so to the outermost ones. The remaining two habitable zones have the same annual seasons, but not at the same time.

His use of the word hemisphere clearly indicates he believed the whole was a sphere.

[David Atherton]

If one wants to use Pliny the elder as evidence, go to book II of his Natural History:

The world appears round like a perfect sphere...The rising and setting of the sun leave us in no doubt that the world is in this shape and that it revolves eternally, without rest and at an indescribable speed, each revolution taking twenty-four hours.

Written in the 70's A.D. the above quote leaves no doubt that most learned 1st century Romans took it for granted the earth was round.

[Heliodromus]

David - thanks for those references.

After searching for more information on Pomponius Mela, I came across this page which gives a very useful list of citations on changing views on the earth's shape:

http://www.ethicalatheist.com/docs/flat_earth_myth_ch5.html

I stand corrected that it does seem that (at least among intellectuals) the shape of the earth was apparently well established as round by Roman times, although there seems to have been a much longer debate about what was on the bottom side of the earth. The notion of the "antipodes" - people who inhabited the underside of the earth, walking upside down, was rejected long after it was agreed that the earth was round. Perhaps descriptions of the extremities of the earth, neighboring the sky, can therefore best be squared with this sort of transitional model where earth was round but where there was a distinct "top" where the land and people where (and maybe those odd sounding antipodes on the bottom). In this view (picture a side view of a plum pudding with custard on the top) the "edges" could indeed be considered closer to the "sky"/heavens.

However, while this knowledge appears to have been well established, that doesn't seem to have prevented others from not believing it at quite late a date, with one notable non-believer being Lactantius who was tutor to Constantine I's son Crispus. The question then remains - what did the common man in the street believe.

Ben

[David Atherton]

I wouldn't be surprised that most Romans believed the same as Mela and Pliny. Anyone who lived near a port could watch the ships heading out to sea and see the last part of a ship to disappear over the horizon was the mast!

[Heliodromus]

I wouldn't be surprised that most Romans believed the same as Mela and Pliny. Anyone who lived near a port could watch the ships heading out to sea and see the last part of a ship to disappear over the horizon was the mast!

Some curvature is definitely self-evident, but Pliny did note a difference in opinion between learned men and the "common herd" :

"Here there is a mighty battle between learning on one side and the common herd on the other: the theory being that human beings are distributed all round the earth and stand with their feet pointing towards each other, and that the top of the sky is alike for them all and the earth trodden under foot at the centre in the same way from any direction, while ordinary people enquire why the persons on the opposite side don't fall off - just as if it were not reasonable that the people on the other side wonder that we do not fall off.  There is an intermediate theory that is acceptable even to the unlearned crowd - that the earth is of the shape of an irregular globe, resembling a pine cone, yet nevertheless is inhabited all round." (Natural History, LXV - [115])

Ben

[Numerianus]

Tacitus was acquainted with Pliny.  Apparently, he was an  educated person and interested
in natural science  as we can conclude  from his information 
about certain observable l phenomena  (e.g., white nights) which required explanations.
So his words should be interpreted correctly. Probably, he believed that the Earth is an ellipsoid, more flat in Polar regions.   
Such a form could explain easier  the difference of  the durations of days and nights. 
 

[Retrospectator]

It appears to me that Tacitus' model was based on the conditions in Britain around midsummer - around midwinter there would be more hours of darkness - an effect caused by the Earth's tilt which was not apparently discovered until hundreds of years after Tacitus. It may be fairer to Tacitus then if we assume that he had read Pliny but was unable to explain or reconcile these extreme conditions in Britain with Pliny's model, and may have simply found the phenomenon easier to explain in terms of the 'flat-Earth' model.  

[Retrospectator]

The comparison of Constantine to the gods from far flung corners (or rather edges!) of the world is obviously panegyrical hyperbolae, but I'd have to guess that the world view it is built on must have been assumed as a common reference with it's intended audience.

Indeed. Also, those members of what Pliny describes as the "common herd" who were familiar with the 'new' theory would have been well acquainted with the idea of a flat Earth in any case.

[Retrospectator]

One more note about Tacitus. In this translation of Germania 45, the word "globe" appears in Tacitus' description of the Earth:

"Beyond the Suiones is another sea, one very heavy and almost void of agitation; and by it the whole globe is thought to be bounded and environed, for that the reflection of the sun, after his setting, continues till his rising, so bright as to darken the stars. To this, popular opinion has added, that the tumult also of his emerging from the sea is heard, that forms divine are then seen, as likewise the rays about his head."

I think this was written around the same time as his 'Agricola'. It would be interesting to check the Latin, to see if Tacitus did indeed describe the Earth as a sphere here.

I quote from here: http://www.fordham.edu/halsall/basis/tacitus-germanygord.html

[Robert_Brenchley]

The description is ambiguous, to say the least, in translation at any rate. He seems to be describing an earthly sea, yet it 'bounds' and 'environs' the globe. It sounds as though it could be a situation where a minority understood, intellectually, that the earth was round, but were still trying to describe it within the parameters of flat-earth thinking.