3a -edges. This is not such a great answer. One could have an infinite flat plane for example (thus being flat with no edges). Similarly, one could have a hemisphere (not flat but with edges).
I agree that “edges” is a weaker implication of flat-earth than the others—but I don’t think it’s unjustified. For one thing, the atmosphere is not purely transparent, so it should be impossible to see the sun through it if it were infinite in (horizontal) extent; for another, the sun has to come up somewhere.
These challenges could be evaded by videogame physics, for example, but such would be in conflict with human intuition.
3a -edges. This is not such a great answer. One could have an infinite flat plane for example (thus being flat with no edges). Similarly, one could have a hemisphere (not flat but with edges).
I agree that “edges” is a weaker implication of flat-earth than the others—but I don’t think it’s unjustified. For one thing, the atmosphere is not purely transparent, so it should be impossible to see the sun through it if it were infinite in (horizontal) extent; for another, the sun has to come up somewhere.
These challenges could be evaded by videogame physics, for example, but such would be in conflict with human intuition.