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This essay reminds me of George Box's famous and often misused statement that "All models are wrong, but some are useful." A spherical earth model is useful an
by simulate 10y ago
This essay reminds me of George Box's famous and often misused statement that "All models are wrong, but some are useful."
A spherical earth model is useful and a flat earth model is not. Also, as Asimov explains here, wrong is relative and a spherical model of the earth is much less wrong than a flat earth model.
- nitrogen 10y agoIn fairness, a flat earth model is still useful for navigation within limited distances.
- deleted 10y ago[deleted]
- 13of40 10y agoIn fairness, the vast majority of the models of the earth people use day-to-day are flat. Case in point: https://www.google.com/maps/@43.0279156,-94.0814245,3z https://www.google.com/maps/@43.0279156,-94.0814245,3z
- Double_Cast 10y agoxkcd relevant to this thread. https://xkcd.com/1318/ https://xkcd.com/1318/
- pdonis 10y agoThis doesn't model the earth's surface as flat. It uses a distorted flat map to model the actual curved geometry of the earth's surface. If the earth were actually flat, the flat map wouldn't be distorted.
- 13of40 10y agoMy point is that Google Maps is possibly the most widely used model of the earth we have, and there's no use case for it where the curvature of the earth comes into play.
- Natanael_L 10y agoThe projection chosen IS the model, and we chose a useful one - and that projection is flat. Is paper maps not models of the real world?
- pdonis 10y ago> The projection chosen IS the model Not if you're going to say the projection is flat. If the projection is flat, and the projection is the model, then I should be able to lay a flat ruler, appropriately scaled, between any two points on the flat map and read off the actual distance between those two points. But I can't do that; and the model knows I can't do that. The model tells me to take the coordinates on the map of two points and plug them into a complicated mathematical formula if I want to get the actual distance between them. So the model is not flat in the sense that matters--in the predictions it makes for distances between points.
- zardo 10y ago>Not if you're going to say the projection is flat. If the projection is flat, and the projection is the model, then I should be able to lay a flat ruler, appropriately scaled, between any two points on the flat map and read off the actual distance between those two points. Is a constant distance metric part of the definition of flat? Why don't the grid lines on the map count as an appropriately scaled ruler?
- pdonis 10y ago> Is a constant distance metric part of the definition of flat? Yes. Otherwise "flat" would have no meaning; we can always make a flat map of any surface, if we are willing to allow the distance metric to be distorted to any extent we like, so every possible surface would be "flat".
- schoen 10y agoYou can even use a flat Earth model for navigation over long distances -- you just might not get the most optimal route, and your map projection (if you're using a map!) will distort something. But it might not be something that you're very concerned about for your particular navigation purposes. https://en.wikipedia.org/wiki/Theorema_Egregium https://en.wikipedia.org/wiki/Theorema_Egregium
- nitrogen 10y agoWithout fail, every few weeks to months I come across an entire branch of science or mathematics I never even suspected existed. Thanks!
- ThomPete 10y agoFlat earth is totally fine as long as you need to simply go from village a to b and it's not too much of a distance. So all models are wrong but some are indeed useful. Darwins theory (and later modernizations) are indeed wrong (as in not true) but it's the most useful model we have.
- pdonis 10y ago> Darwins theory (and later modernizations) are indeed wrong (as in not true) Not true in what sense?
- EGreg 10y agoIn that they don't match reality.
- pdonis 10y agoIn what sense do they not match reality?
- ThomPete 10y agoThey are reductions of reality. A decision to look at things a certain way.
- pdonis 10y ago> They are reductions of reality Sure, but that doesn't mean they don't match reality. It just means they don't match all of reality; they leave information out. Of course all of our models have to leave information out, I agree with that. But that's a separate question from the question of whether the information a given model includes matches the portion of reality it is intended to model--or, better, to how good an approximation a given model matches the portion of reality it is intended to model. That's the whole point of Asimov's essay.
- 10y ago
- simonh 10y ago> a flat earth model is not I'd highly recommend reading the article again a little more carefully.
- slavik81 10y agoWhen I worked on mapping software, we actually had a few options for calculating angles and distances. If points were near enough, we'd use a flat Earth approximation to speed up the calculations.