4 ms·

Ask HN: What every teenager of 2020's knows but minds of ancient Greece did not?

1 points by eimrine 4y ago

db48x 4y ago
The Sun–Earth distance is 93 million miles. The ancient Greeks could not even estimate this value.
- Someone 4y ago
  I don’t think every teenager knows that. It wouldn’t even surprise me if Posidonious’ estimate of about half the real distance were better than what you would get by averaging the responses from a representative sample of teenagers (https://en.wikipedia.org/wiki/Posidonius#Astronomy_and_Meteorology https://en.wikipedia.org/wiki/Posidonius#Astronomy_and_Meteo...)
  - eimrine 4y ago
    > > The Sun–Earth distance is 93 million miles. > I don’t think every teenager knows that. Teenage respondents have a good chance of remembering that it takes 8 minutes for light to travel from the Sun to the Earth.
    - beardyw 4y ago
      But do they know the speed of light?
    - db48x 4y ago
      I think that is another candidate for a fact easily remembered by the average teenager. Top five at least, and not known to the ancient Greeks.
    - Someone 4y ago
      That’s a lot likelier, yes. I may be pessimistic, but I think that still wouldn’t help them answer “How far is the sun from earth?” because I doubt your average teenager can compute “8 minutes times 300,000 km/s in km”, let alone “8 minutes times 186,300 miles/s in miles”. Their phone can, but their phone also can answer “How far is the sun from earth?” directly.
      - db48x 4y ago
        The computation is irrelevant. “Light from the Sun takes 8 minutes to reach the Earth” is a true fact known to teenagers which was not known to the ancient Greeks.
  - db48x 4y ago
    You’re right that I should be a little more precise, and state that their estimates were very, very bad and that the limitations were due primarily to the crudity of their instruments (no telescopes yet). But I think that amongst the astronomical facts taught to children it will be the most easily remembered. Well, perhaps the number of planets will be more easily remembered, but that has varied over time and the ancient Greeks had as good a number for that as we do.
    - Someone 4y ago
      My comment was way less on what the Greeks knew than on what I think “every teenager” knows. In my reading of the question, the bar is a lot higher than “most easily remembered”, even loosening (as we should; there’s basically nothing that truly _every_ teenager knows) “every teenager knows” to “a majority of teenagers know” I can’t find a specific paper on teenager’s knowledge, but if you Google a bit, you get hits such as https://koreascience.kr/article/JAKO201008863879014 https://koreascience.kr/article/JAKO201008863879014, which says “Some teachers thought that the distance to Neptune is farther than the distance from Earth to the nearest star”. Those are elementary school teachers that may not be university schooled, but I would guess they education-wise score in the upper half of the population. https://www.researchgate.net/publication/247914140_The_initial_knowledge_state_of_high_school_astronomy_students https://www.researchgate.net/publication/247914140_The_initi... also is revealing about what teenagers know, but focuses a bit more on understanding.
- eimrine 4y ago
  wrong, they figured this up using trigonometry having 10x mistake as an outcome from inability to measure disc of Sun in angular units with enough precision.
Someone 4y ago
If you’re aiming for “as far as we know, not a single Greek suggested” things like that the earth revolves around the sun” or “everything is made of atoms” do not qualify, and even “that atoms can be split” wouldn’t (https://en.wikipedia.org/wiki/Atomism https://en.wikipedia.org/wiki/Atomism proposes “that the physical universe is composed of fundamental indivisible components known as atoms”, but the Greeks did not make the mistake of calling what we call atoms atoms) Chemistry is rather new, though. I don’t think any Greek remotely knew that water is H₂O, and also guess the majority of teenagers would know. The existence of more than 5 planets also is a likely candidate. The Greeks didn’t know that, and knowledge of that in the English-speaking world under teenagers is helped by the fact that one of them is called Uranus.
elmerfud 4y ago
That chocolate, potatoes, avocado, corn and tomato are things. Along with the entirety of the America's.
ZeroGravitas 4y ago
That actual democracy can work?
- leed25d 4y ago
  I would say that the jury is still out on that one.
suprjami 4y ago
That light comes from the light source and is reflected into our eyes, allowing us to see. Not that our eyes are the light source, as Plato wrote in the ~300BCs.

1 points by eimrine 4y ago

db48x 4y ago

The Sun–Earth distance is 93 million miles. The ancient Greeks could not even estimate this value.

Someone 4y ago
I don’t think every teenager knows that. It wouldn’t even surprise me if Posidonious’ estimate of about half the real distance were better than what you would get by averaging the responses from a representative sample of teenagers (https://en.wikipedia.org/wiki/Posidonius#Astronomy_and_Meteorology https://en.wikipedia.org/wiki/Posidonius#Astronomy_and_Meteo...)
- eimrine 4y ago
  > > The Sun–Earth distance is 93 million miles. > I don’t think every teenager knows that. Teenage respondents have a good chance of remembering that it takes 8 minutes for light to travel from the Sun to the Earth.
  - beardyw 4y ago
    But do they know the speed of light?
  - db48x 4y ago
    I think that is another candidate for a fact easily remembered by the average teenager. Top five at least, and not known to the ancient Greeks.
  - Someone 4y ago
    That’s a lot likelier, yes. I may be pessimistic, but I think that still wouldn’t help them answer “How far is the sun from earth?” because I doubt your average teenager can compute “8 minutes times 300,000 km/s in km”, let alone “8 minutes times 186,300 miles/s in miles”. Their phone can, but their phone also can answer “How far is the sun from earth?” directly.
    - db48x 4y ago
      The computation is irrelevant. “Light from the Sun takes 8 minutes to reach the Earth” is a true fact known to teenagers which was not known to the ancient Greeks.
- db48x 4y ago
  You’re right that I should be a little more precise, and state that their estimates were very, very bad and that the limitations were due primarily to the crudity of their instruments (no telescopes yet). But I think that amongst the astronomical facts taught to children it will be the most easily remembered. Well, perhaps the number of planets will be more easily remembered, but that has varied over time and the ancient Greeks had as good a number for that as we do.
  - Someone 4y ago
    My comment was way less on what the Greeks knew than on what I think “every teenager” knows. In my reading of the question, the bar is a lot higher than “most easily remembered”, even loosening (as we should; there’s basically nothing that truly _every_ teenager knows) “every teenager knows” to “a majority of teenagers know” I can’t find a specific paper on teenager’s knowledge, but if you Google a bit, you get hits such as https://koreascience.kr/article/JAKO201008863879014 https://koreascience.kr/article/JAKO201008863879014, which says “Some teachers thought that the distance to Neptune is farther than the distance from Earth to the nearest star”. Those are elementary school teachers that may not be university schooled, but I would guess they education-wise score in the upper half of the population. https://www.researchgate.net/publication/247914140_The_initial_knowledge_state_of_high_school_astronomy_students https://www.researchgate.net/publication/247914140_The_initi... also is revealing about what teenagers know, but focuses a bit more on understanding.
eimrine 4y ago
wrong, they figured this up using trigonometry having 10x mistake as an outcome from inability to measure disc of Sun in angular units with enough precision.

Someone 4y ago

If you’re aiming for “as far as we know, not a single Greek suggested” things like that the earth revolves around the sun” or “everything is made of atoms” do not qualify, and even “that atoms can be split” wouldn’t (https://en.wikipedia.org/wiki/Atomism https://en.wikipedia.org/wiki/Atomism proposes “that the physical universe is composed of fundamental indivisible components known as atoms”, but the Greeks did not make the mistake of calling what we call atoms atoms) Chemistry is rather new, though. I don’t think any Greek remotely knew that water is H₂O, and also guess the majority of teenagers would know. The existence of more than 5 planets also is a likely candidate. The Greeks didn’t know that, and knowledge of that in the English-speaking world under teenagers is helped by the fact that one of them is called Uranus.

elmerfud 4y ago

That chocolate, potatoes, avocado, corn and tomato are things. Along with the entirety of the America's.

ZeroGravitas 4y ago

That actual democracy can work?

leed25d 4y ago
I would say that the jury is still out on that one.

suprjami 4y ago

That light comes from the light source and is reflected into our eyes, allowing us to see. Not that our eyes are the light source, as Plato wrote in the ~300BCs.