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This inspired similarly annoyed responses last time it was posted too. It genuinely surprises me to see that on HN. The whole thing can be summarized as "You mi

This inspired similarly annoyed responses last time it was posted too. It genuinely surprises me to see that on HN. The whole thing can be summarized as "You might think of 'start facing East and go in a straight line' as being the same as 'maintain an Eastern heading', but latitude lines are only straight in the Cartesian abstraction we're used to, and not in reality." I hadn't thought about it before. It's interesting. It's not some kind of cheap or stupid trick intended to embarrass you. The negativity is truly baffling.

ajkjk 2y ago
Well they called it "Go east" so maybe it feels like a trick that they didn't go east? Instead they worded their actual question in a subtly different way and then said "gotcha". It's a cool observation and would have been cool without the pedantry, too.
- brokencode 2y ago
  Did they change the title of the blog post? When I open it, it says “A path from Seattle”. The “Go east” part is only in the Hacker News post.
  - mc10 2y ago
    The Substack version says "Go east from Seattle": https://finmoorhouse.substack.com/p/go-east-from-seattle https://finmoorhouse.substack.com/p/go-east-from-seattle
    - finm 2y ago
      Yes, I changed the title to the linked page to ‘A path from Seattle’ from ‘Go east from Seattle’ because, from reading the comments here, I agree the original title was too misleading. Just updated the title of the Substack post also.
plorkyeran 2y ago
It's a trick question regardless of if the intent was to educate the reader or to make them feel stupid. You have to spot that the question both isn't asking what the title suggests it's asking and that the image isn't actually showing the direction you'd go. People tend not to like trick questions.
hervature 2y ago
I don't think it is negativity. Someone else already called it out, but if you were to face east and then travel in a straight line, you would leave Earth's orbit. Thus, the question inherently is taking Earth into consideration. Their definition of "most obvious" is strange because you would encode a globe using spherical coordinates. A "straight line" East in spherical coordinates could be argued to be keeping the polar angle constant and increasing the azimuthal angle which would land you in France. The crux of the disagreement is what "most obvious" means.
- brokencode 2y ago
  Idk, I think it’s pretty clear based on the description what they mean. For one, the problem description says the straight line is “along the Earth’s surface” so I don’t think you can reasonably think it might go into space. And to me it seems reasonable to say a straight line means not turning. I personally imagined getting in a plane and going straight forward, assuming there is no wind to blow me off course. That is just the common understanding of straight. If somebody asks you to walk in a straight line, do you ask them what coordinate system they’re using? No, you walk forward without turning. I guess “most obvious” can always be up to interpretation, though.
  - hervature 2y ago
    I think if you were to ask someone not trained in navigation "to fly straight" between two points on the globe, they are probably not going to come up with the concept of great circles and most likely will end up turning a bunch during their flight "to fly straight". I could be wrong but I think "most obvious" if we are defining it as "the most natural thing most people would do without explicit training" then the article is wrong and this thread would agree with this conclusion. I don't disagree that it is possible to deduce the great circle if you think about it and have the knowledge to coordinate systems. But why even ask the question this way when you can get to the core of the question by explicitly asking "Along the great circle that reaches its max latitude at Seattle, what's the next country it touches going eastward from Seattle?" This would yield many more correct answers and why people think its mostly wordplay (because it is).
karaterobot 2y ago
HN is full of people who like to be the "well actually" guy, and they're all getting well actually'd by this article. Of course they're annoyed. It must be just awful.
- lxgr 2y ago
  If you ask a question to which the answer is "no, actually...", don't be upset when you get a lot of "well, actually actually" retorts, especially on this site :) And don't bring a geodesic to a semantics fight!
- re 2y ago
  After this, let's have a calm discussion about whether an airplane can take off from a treadmill that exactly matches the plane's wheel's speed in the reverse direction.
  - RaftPeople 2y ago
    I enjoyed many weeks of debate on a different website about that.
tacitusarc 2y ago
As they state at the bottom, they are referring specifically to geodesics when they mean straight line. They then rule out the due east curve, despite stating you must travel due east. They claim this is because to do so would make the line no longer straight, but this claim is utterly nonsensical in the context of three dimensional geometries. This is a puzzle born of a misunderstanding of three dimensional Euclidean geometry.
lxgr 2y ago
> start facing East and go in a straight line This is where the trick is hidden: To do this, you'd generally require a spaceship (or a very impressive ladder) :)

ajkjk 2y ago

Well they called it "Go east" so maybe it feels like a trick that they didn't go east? Instead they worded their actual question in a subtly different way and then said "gotcha". It's a cool observation and would have been cool without the pedantry, too.

brokencode 2y ago
Did they change the title of the blog post? When I open it, it says “A path from Seattle”. The “Go east” part is only in the Hacker News post.
- mc10 2y ago
  The Substack version says "Go east from Seattle": https://finmoorhouse.substack.com/p/go-east-from-seattle https://finmoorhouse.substack.com/p/go-east-from-seattle
  - finm 2y ago
    Yes, I changed the title to the linked page to ‘A path from Seattle’ from ‘Go east from Seattle’ because, from reading the comments here, I agree the original title was too misleading. Just updated the title of the Substack post also.

plorkyeran 2y ago

It's a trick question regardless of if the intent was to educate the reader or to make them feel stupid. You have to spot that the question both isn't asking what the title suggests it's asking and that the image isn't actually showing the direction you'd go. People tend not to like trick questions.

hervature 2y ago

I don't think it is negativity. Someone else already called it out, but if you were to face east and then travel in a straight line, you would leave Earth's orbit. Thus, the question inherently is taking Earth into consideration. Their definition of "most obvious" is strange because you would encode a globe using spherical coordinates. A "straight line" East in spherical coordinates could be argued to be keeping the polar angle constant and increasing the azimuthal angle which would land you in France. The crux of the disagreement is what "most obvious" means.

brokencode 2y ago
Idk, I think it’s pretty clear based on the description what they mean. For one, the problem description says the straight line is “along the Earth’s surface” so I don’t think you can reasonably think it might go into space. And to me it seems reasonable to say a straight line means not turning. I personally imagined getting in a plane and going straight forward, assuming there is no wind to blow me off course. That is just the common understanding of straight. If somebody asks you to walk in a straight line, do you ask them what coordinate system they’re using? No, you walk forward without turning. I guess “most obvious” can always be up to interpretation, though.
- hervature 2y ago
  I think if you were to ask someone not trained in navigation "to fly straight" between two points on the globe, they are probably not going to come up with the concept of great circles and most likely will end up turning a bunch during their flight "to fly straight". I could be wrong but I think "most obvious" if we are defining it as "the most natural thing most people would do without explicit training" then the article is wrong and this thread would agree with this conclusion. I don't disagree that it is possible to deduce the great circle if you think about it and have the knowledge to coordinate systems. But why even ask the question this way when you can get to the core of the question by explicitly asking "Along the great circle that reaches its max latitude at Seattle, what's the next country it touches going eastward from Seattle?" This would yield many more correct answers and why people think its mostly wordplay (because it is).

karaterobot 2y ago

HN is full of people who like to be the "well actually" guy, and they're all getting well actually'd by this article. Of course they're annoyed. It must be just awful.

lxgr 2y ago
If you ask a question to which the answer is "no, actually...", don't be upset when you get a lot of "well, actually actually" retorts, especially on this site :) And don't bring a geodesic to a semantics fight!
re 2y ago
After this, let's have a calm discussion about whether an airplane can take off from a treadmill that exactly matches the plane's wheel's speed in the reverse direction.
- RaftPeople 2y ago
  I enjoyed many weeks of debate on a different website about that.

tacitusarc 2y ago

As they state at the bottom, they are referring specifically to geodesics when they mean straight line. They then rule out the due east curve, despite stating you must travel due east. They claim this is because to do so would make the line no longer straight, but this claim is utterly nonsensical in the context of three dimensional geometries. This is a puzzle born of a misunderstanding of three dimensional Euclidean geometry.

lxgr 2y ago

> start facing East and go in a straight line This is where the trick is hidden: To do this, you'd generally require a spaceship (or a very impressive ladder) :)