Erana said:
You claim to know the Truth? Interesting.
You misunderstood. I claim that I search for the truth, constantly refining my knowledge to separate false statements and beliefs from those that I can show to be true.
But since we as humans are fallible, we can only asymptotically approach the truth. Some parts we know better, some parts we are just finding out and of some we currently have no idea. All truth known by humans is provincial, by the very nature of scientific method and human fallibility.
I take everything with a grain of salt. And once again, I pull out the, "prove the earth is round" argument.
Very well then: We have the hyphothesis, 'Earth is round'. How would we go about disproving that?
Easy. If the earth is not round, then at different latitudes (like say... Cairo and Stockholm), when measured at the same local time (EDIT:Fixed that. A better comparison would have been two cities at the same longitude) the shadow of an object of equal heigh from the ground up should be equally long. This would be because the sunlight would come at an equal angle to both objects.
We find this to be false. The shadows are of different lenght. Therefore, either sunlight does not travel in linear fashion (something between the sun and stockholm is causing the light to bend whereas this effect is mysteriously missing from between sun and Cairo. Or vice versa) or the surface of the earth has some curvature.
Also, assuming earth is not round or curved, how does one explain the following observation:
Upon looking at the horizon while at sea, the mast of ships approaching from 'behind' the horizon are seen first, before the rest of the ship? Indeed, how does on explain horizon 'blocking' view at all? With a sufficiently advanced telescope, it should be possible to look from one side of the Pacific Ocean to the other side (USA to China for example) in a straight line, if the Earth were flat instead of round.
Yet this is impossible. Either Earth has curvature, or light bends away from earth's surface for no apparent reason at all. Upon completion of other tests, this mysterious curvature of light away from Earth's surface is not supported by empirical evidence. Light travels at a straight line as far as the instruments can tell.
As far as anything can be known, this is pretty much the proof you requested.
Using science, you can build a case filled with a huge amount of circumstantial evidence, but unless someone flies me up into space to see with my own eyes, how can one truely prove if there's a curve to the world?
Just a thought.
Why not take one step further? How could you trust your own eyes should you actually make it to Earth's orbit? That too would be circumstancial evidence as you seem to be using that word. You cannot prove your eyes give you accurate information.
You have to assume they do, in order to function in what we perceive to be reality.
Science builds from that lonely assumption, requesting proof and evidence until things can be proven and thus known, to the extent that anything can be known.
So if you could trust your own eyes to show you the reality of Earth's roundness from the orbit, why would you not trust them to give you accurate information down on earth? In reference to the shadow test and horizon problem: If you cannot believe the results of these tests, seen with your own eyes, why would you suddenly believe your eyes upon reaching planetary orbit - Your eyes are still seeing the exact same thing, curvature of the Earth.