Sunday, 5 November 2017

Lactantius: why the earth is not round.



It is nonsense to think that the idea of a flat earth was refuted by Columbus, when he tried to find a route to India through a western passage.  Still, the idea of a round earth was far from universally accepted and one of those who could not believe it was the Christian writer Lactantius (c. 250 – c. 325). His major work is the Institutiones Divinae, an apology for Christianity. In book three he is trying to show that the idea of a round world is nonsense. There were indeed weaknesses in the arguments defending a round world. The idea was – at least that described and refuted by Lactantius – that the world was a steady ball in the centre of a round universe and that sun, moon and stars are revolving around the earth. It is as if the earth is at the centre inside a football and that this ball turning around us and we are looking at the inside on which stars, sun and moon are painted. The mathematical problems of explaining all the motions with the assumption that the earth itself is steady at the centre are unsurmountable. We may laugh now at the way Lactantius is defending a flat earth, but suppose we were contemporaries, I wonder how many of us would not have been convinced by his arguments.

Lactantius. Institutiones Divinae, 3.24 : De antipodibus, de coelo ac sideribus.

1)            Quid illi, qui esse contrarios vestigiis nostris Antipodas putant, num aliquid loquuntur? aut est quisquam tam ineptus, qui credat esse homines, quorum vestigia sint superiora, quam capita? aut ibi, quae apud nos iacent, inversa pendere? fruges et arbores deorsum versus crescere? pluvias, et nives, et grandinem sursum versus cadere in terram? Et miratur aliquis, hortos pensiles inter septem mira narrari, cum philosophi et agros, et maria, et urbes, et montes pensiles faciant? Huius quoque erroris aperienda nobis origo est. Nam semper eodem modo falluntur. Cum enim falsum aliquid in principio sumpserint, veri similitudine inducti, necesse est eos in ea, quae consequuntur, incurrere. Sic incidunt in multa ridicula; quia necesse est falsa esse, quae rebus falsis congruunt. Cum autem primis habuerint fidem, qualia sint ea, quae sequuntur, non circumspiciunt, sed defendunt omni modo; cum debeant prima illa, utrumne vera sint, an falsa, ex consequentibus iudicare.

vestigium: footprint
ineptus: silly
quae apud nos iacent, inversa pendere?: which are lying by us, are hanging upside down?  (e.g. a cloth on a table)
deorsum versus: downwards
nix nivis (f.): snow
grando grandinis (f.): hail
sursum versus: upwards
hortos pensiles: hanging gardens (of Babylon)
cum philosopi…faciant: when philosophers invent
aperienda nobis origo: the origin is to be uncovered by us
falluntur: go wrong
sumpserint: have assumed
veri similitudine inducti: having it put forward as truth
circumspiciunt: look carefully

2             Quae igitur illos ad Antipodas ratio perduxit? Videbant siderum cursus in occasum meantium; solem atque lunam in eamdem partem semper occidere, atque oriri semper ab eadem. Cum autem non perspicerent, quae machinatio cursus eorum temperaret, nec quomodo ab occasu ad orientem remearent, coelum autem ipsum in omnes partes putarent esse devexum, quod sic videri, propter immensam latitudinem necesse est: existimaverunt, rotundum esse mundum sicut pilam, et ex motu siderum opinati sunt coelum volvi, sic astra solemque, cum occiderint, volubilitate ipsa mundi ad ortum referri. Itaque et aereos orbes fabricati sunt, quasi ad figuram mundi, eosque caelarunt portentosis quibusdam simulacris, quae astra esse dicerent. Hanc igitur coeli rotunditatem illud sequebatur, ut terra in medio sinu eius esset inclusa. Quod si ita esset, etiam ipsam terram globo similem; neque enim fieri posset, ut non esset rotundum, quod rotundo conclusum teneretur. Si autem rotunda etiam terra esset, necesse esse, ut in omnes coeli partes eamdem faciem gerat, id est montes erigat, campos tendat, maria consternat. Quod si esset, etiam sequebatur illud extremum, ut nulla sit pars terrae, quae non ab hominibus caeterisque animalibus incolatur. Sic pendulos istos Antipodas coeli rotunditas adinvenit.

siderum cursus in occasum meantium: the course of the wandering start to the west
machinatio –onis (f.): mechanism
remeo: go again, return
devexus: shelving
pila: ball
opinati sunt coelum volvi:  they think that the sky is turning
volubilitate ipsa mundi: by just the vast motion of the universe (not `the world’!)
aereos orbes: indeed such mechanical devises depicting the universe in order to explain its motion have been discovered.
caelo: to engrave
portentosis quibusdam simulacris: some horrible images (Why horrible? Because they didn’t really look like stars? Or is it just derogatory?)
Hanc igitur coeli rotunditatem illud sequebatur: this followed from that roundness of the sky
in medio sinu: at the centre of the curved surface
ut non esset rotundum, quod rotundo conclusum teneretur: i.e. because the sky is round, the earth must be round too
ut in omnes coeli partes eamdem faciem gerat: that it has the same appearance  towards all part of the sky (But like the idea that the earth must be round because the sky is round, this idea too carries some aesthetic reasoning.)
erigo erexi erectum: to lift up
tendo tetendi tentum (tensum): to stretch out
consterno constravi constratum: to spread
pendulus: hanging down

3             Quod si quaeras ab iis, qui haec portenta defendunt, quomodo non cadunt omnia in inferiorem illam coeli partem; respondent, hanc rerum esse naturam, ut pondera in medium ferantur, et ad medium connexa sint omnia, sicut radios videmus in rota; quae autem levia sunt, ut nebula, fumus, ignis, a medio deferantur, ut coelum petant. Quid dicam de iis nescio, qui, cum semel aberraverint, constanter in stultitia perseverant, et vanis vana defendunt; nisi quod eos interdum puto, aut ioci causa philosophari, aut prudentes et scios mendacia defendenda suscipere, quasi ut ingenia sua in malis rebus exerceant, vel ostendant. At ego multis argumentis probare possem, nullo modo fieri posse, ut coelum terra sit inferius, nisi et liber iam concludendus esset, et adhuc aliqua restarent, quae magis sunt praesenti operi necessaria. Et quoniam singulorum errores percurrere non est unius libri opus, satis sit pauca enumerasse, ex quibus possit qualia sint caetera intelligi.

haec portenta: these horrible things
ut pondera in medium ferantur: that heavy things go to the centre (This idea comes from Aristotle and it explains gravity.)
radios in rota: spokes in a wheel
defero detuli delatum: go away from
peto: to seek, strive
semel: once
interdum: now and then
ioci causa: for fun
aut prudentes et scios mendacia defendenda suscipere: or clever and on purpose take up to defend lies
ingenia sua: their intelligence
ostendo ostendi ostentum: to show
nisi et liber (= chapter) iam concludendus esset: a very weak reason for not bringing forward arguments for a flat earth!
quoniam: whereas



Translated by William Fletcher. From Ante-Nicene Fathers, Vol. 7 (1886)

How is it with those who imagine that there are antipodes opposite to our footsteps? Do they say anything to the purpose? Or is there any one so senseless as to believe that there are men whose footsteps are higher than their heads? Or that the things which with us are in a recumbent position, with them hang in an inverted direction? That the crops and trees grow downwards? That the rains, and snow, and hail fall upwards to the earth? And does any one wonder that hanging gardens are mentioned among the seven wonders of the world, when philosophers make hanging fields, and seas, and cities, and mountains? The origin of this error must also be set forth by us. For they are always deceived in the same manner. For when they have assumed anything false in the commencement of their investigations, led by the resemblance of the truth, they necessarily fall into those things which are its consequences. Thus they fall into many ridiculous things; because those things which are in agreement with false things, must themselves be false. But since they placed confidence in the first, they do not consider the character of those things which follow, but defend them in every way; whereas they ought to judge from those which follow, whether the first are true or false.

What course of argument, therefore, led them to the idea of the antipodes? They saw the courses of the stars travelling towards the west; they saw that the sun and the moon always set towards the same quarter, and rise from the same. But since they did not perceive what contrivance regulated their courses, nor how they returned from the west to the east, but supposed that the heaven itself sloped downwards in every direction, which appearance it must present on account of its immense breadth, they thought that the world is round like a ball, and they fancied that the heaven revolves in accordance with the motion of the heavenly bodies; and thus that the stars and sun, when they have set, by the very rapidity of the motion of the world are borne back to the east. Therefore they both constructed brazen orbs, as though after the figure of the world, and engraved upon them certain monstrous images, which they said were constellations. It followed, therefore, from this rotundity of the heaven, that the earth was enclosed in the midst of its curved surface. But if this were so, the earth also itself must be like a globe; for that could not possibly be anything but round, which was held enclosed by that which was round. But if the earth also were round, it must necessarily happen that it should present the same appearance to all parts of the heaven; that is, that it should raise aloft mountains, extend plains, and have level seas. And if this were so, that last consequence also followed, that there would be no part of the earth uninhabited by men and the other animals. Thus the rotundity of the earth leads, in addition, to the invention of those suspended antipodes.

But if you inquire from those who defend these marvellous fictions, why all things do not fall into that lower part of the heaven, they reply that such is the nature of things, that heavy bodies are borne to the middle, and that they are all joined together towards the middle, as we see spokes in a wheel; but that the bodies which are light, as mist, smoke, and fire, are borne away from the middle, so as to seek the heaven. I am at a loss what to say respecting those who, when they have once erred, consistently persevere in their folly, and defend one vain thing by another; but that I sometimes imagine that they either discuss philosophy for the sake of a jest, or purposely and knowingly undertake to defend falsehoods, as if to exercise or display their talents on false subjects. But I should be able to prove by many arguments that it is impossible for the heaven to be lower than the earth, were it not that this book must now be concluded, and that some things still remain, which are more necessary for the present work. And since it is not the work of a single book to run over the errors of each individually, let it be sufficient to have enumerated a few, from which the nature of the others may be understood.