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The most fascinating thing for me is that at that time, he was able to conceptualize that people could walk on the moon, and that it was big enough to have a wa

• jaggederest 8y ago
  They had geometry, you can figure out fairly accurately (within tens to thousands of miles) how large and how far away the moon is based on parallax and the kind of math that Eratosthenes used to calculate the circumference of the earth 400 years earlier. The only celestial bodies that you can't do that with are the ones that are point sources to the naked eye, like the planets. Those take lenses and telescopes.
  • kgc 8y ago
    It's sad that ancient civilizations knew the Earth was round, yet we still have that debate in some communities today...
    • ekianjo 8y ago
      I dont think "ancient civilizations" is a fair description. Some of them only, and few compared to the number of civilizations. And even in the ones where it was known, that knowledge was most probably only shared within a small group of scholars.
      • benbreen 8y ago
        Your comment got me wondering about how widely Hellenistic cosmological models of the spherical earth circulated. I, like you, assumed it was only known to a small group of scholars like Eratosthenes. But digging around a bit, it seems like any literate person in the Mediterranean basin and Middle East during the time of the early Roman Empire could've been exposed to the idea of a spherical earth, via Aristotle or the Pythagoreans. Or at least so says Wikipedia's (surprisingly good) page for the history of the spherical earth model: "After the 5th century BC, no Greek writer of repute thought the world was anything but round." [1] The page documents how this then filtered into Roman and early Muslim astronomical traditions. Granted, since only a small percentage of people in these societies were literate, it was probably true that most people in, say, the Roman or Sasanian empires thought the earth was flat. But given what we know about the ways that premodern books were read (often in public, sometimes to a large groups of people) it seems to me like an open question. There's also this very interesting aside about the possibility that the Phoenicians also knew the earth was round, perhaps even predating the Greeks: "In The Histories, written 431–425 BC, Herodotus cast doubt on a report of the Sun observed shining from the north. He stated that the phenomenon was observed during a circumnavigation of Africa undertaken by Phoenician explorers employed by Egyptian pharaoh Necho II c. 610–595 BC (The Histories, 4.42) who claimed to have had the Sun on their right when circumnavigating in a clockwise direction. To modern historians, these details confirm the truth of the Phoenicians' report and even open the possibility that the Phoenicians knew about the spherical model. However, nothing certain about their knowledge of geography and navigation has survived." [1] https://en.wikipedia.org/wiki/Spherical_Earth#History https://en.wikipedia.org/wiki/Spherical_Earth#History
        • jacobush 8y ago
          Even if they were illiterate, it's entirely possible that to the extent people even cared, they knew the Earth is round.
        • jlawson 8y ago
          A globus cruciger is a small sphere with a cross affixed to the top. Christian medieval rulers would hold one as a symbol of dominion over Earth (with the cross dominating the Earth's globe). Even before Christ, they used to just hold globes. It's the same image as that "evil megacorporation controlling the world" hand-holding-Earth image we've all seen before. My point is that they seem to have known continuously since ancient times that the Earth was a sphere. They were using globus crucigers the whole time. Even in the Dark Ages, the Byzantine Emperor had coins made with his image holding such a globe, around 700AD. It seems more like they'd know the Earth was round but really have no reason to care or spend any time thinking about it, the same way we don't spend time talking about the microwave background radiation from the big bang or the structure of our local galactic supercluster. These people didn't even have a standard unit to measure bags of grain from one village to the next. Assuming they had any grain to measure at all. https://en.wikipedia.org/wiki/Globus_cruciger https://en.wikipedia.org/wiki/Globus_cruciger (Incidentally the ritual orb which Elsa must take in Frozen is a politically correct de-Christianized version of this).
        • oblio 8y ago
          > I, like you, assumed it was only known to a small group of scholars like Eratosthenes. But digging around a bit, it seems like any literate person in the Mediterranean basin and Middle East during the time of the early Roman Empire could've been exposed to the idea of a spherical earth, via Aristotle or the Pythagoreans. Don't forget that the literacy rate for pre-modern societies was 10% and probably much lower on average. There were some extreme exceptions, I think the Hebrews had much higher rates, but as a whole, the world's population couldn't even write their own name.
          • ekianjo 8y ago
            Yeah, and let's not forget that level of literacy was among citizens... not even accounting for slaves, which could account for a large part of the populace in some civilizations.
      • jacobush 8y ago
        All sea faring peoples must have known or suspected the Earth is round?
        • Tor3 8y ago
          Yes, agreed. Unless they were ever only sailing short distances and only in their local near-coastline seas (and very local - as soon as you start looking at the sun, moon, stars and planets to get some idea of where you are it's pretty much impossible to not understand that you're not on a flat disc). As for illiteracy - it's not always necessary to be literate in order to know something. In our modern world there's a great many things 'everybody' knows, without necessarily ever having read about it. True things as well as false things, obviously.
    • blauditore 8y ago
      I'm pretty sure most people claiming to be a flat-earthers are either trolls or somehow try to gain something (money, power, or attention) from it.
      • ObsoleteNerd 8y ago
        I used to think that, but lately I'm not so sure. https://www.youtube.com/watch?v=1gHbwT_R9t0 https://www.youtube.com/watch?v=1gHbwT_R9t0
        • rplnt 8y ago
          I would categorize it as the "people making profit" bracket. Selling tickets, merchandise, ... But then there's the group of consumers of course, which is worrying.
      • selestify 8y ago
        I know a flat-earther, and he is definitely not a troll, or pretending in any way.
• 0xBABAD00C 8y ago
  Democritus, who lived many centuries before Lucian, reasoned his way to discovering the concept of atoms, and that the world must be built up from a finite set of small indivisible particles. I find that even more fascinating...
  • deleted 8y ago
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  • charlysl 8y ago
    It is indeed. But even more so for me is that then Epicurus, starting from this, deducted a whole ethic that is essentially modern. If you haven't read it yet, I think you would appreciate an account of the whole story, of how it was supressed by the church for centuries and eventually triumphed: "The Swerve: How the World Became Modern" https://www.amazon.com/Swerve-How-World-Became-Modern/dp/039.. https://www.amazon.com/Swerve-How-World-Became-Modern/dp/039....
• ekianjo 8y ago
  Ancient Greeks were able to determine the diameter of the Earth just by solar and shadows observations, so determining an approximate size of the moon is not something that sounds very improbable, while certainly more difficult.
  • chopin 8y ago
    What's also worth noting and easily observable: I went to Egypt a couple of weeks ago. Around half-moon, my wife noted that the moon was looking strangely to her eyes. I realized that being more south, the terminator on the moon has a much shallower angle than more up in the north where I live. This indicates that the angle of observation has changed and hints also to a spherical earth.
• KnightOfWords 8y ago
  Colonising Venus is a greater leap of imagination, to the best of our knowledge the ancient Greeks had no telescopes so would have only ever seen it as a point of light. > Of course, he seemed to also think that you could walk on the sun, but can't blame him for extending the logic and not knowing that the sun's composition wasn't great for walking. William Herschel, discoverer of Uranus, also speculated that the Sun might be populated. It wasn't until the 19th century that the surface temperature of the Sun was estimated.
  • alistairSH 8y ago
    Lucian wasn't an ancient Greek. He was Syrian and lived in the 2nd century AD. But, your point about a lack of telescopes still stands.
    • jacobolus 8y ago
      Using “Ancient Greeks” in this context doesn’t seem too unreasonable, in the sense of “Greek-speaking province of the Roman Empire”. Greek was also the lingua franca of philosophy, mathematics, etc. in the Eastern Mediterranean for several centuries. If we are talking about astronomy, it is also e.g. common to call Ptolemy a “Greek” astronomer, even though he lived in the Roman province of Egypt.
      • alistairSH 8y ago
        Fair enough. When I hear "Ancient Greece" I generally think of Greece through the Hellenistic period. Though now that I've said that, Lucian would have lived through the Roman annexation of Greece. Really, my point was Lucian lived at the more recent end of antiquity. Humanity's knowledge of the world around them was quite a bit different then than 500 years prior.
      • AlexB138 8y ago
        Well, the Ptolemys were actually Greek though, more specifically Macedonian, and descended from one of the leaders of an army that created the Hellenistic era. I'm not sure we can equate them with a scholar who just happen to speak the same language if we're doing so to qualify people as "Greek". I also feel the need to point out how hilariously pedantic this conversation is, and how much I enjoy that.