Re: flat versus spherical earth. The reason this is so important, is because it goes to the very crux of an individuals empirical based perceptions about the reality which they exist within. If this most core of perceptions is corrupted, then pretty much everything else which builds on top of it will also be corrupted and distorted. This includes thought, emotion and behavior. The perception of flat versus spherical is as important as up versus down and left versus right. I put it to you that the 'shape' of the reality we inhabit is also as obvious as left, right, up or down. No amount of words or sophistry can alter this. A simple experiment to definitively prove that we are not on a spinning sphere traveling at 1000 miles per hour (i.e. approx 24,000 miles traveled per day at the equator) is the following. Find a suitable spot on the ground outside. Jump in the air (vertically up). Just a few inches will do. When you land - measure the distance the ground has traveled under your feet (while you were in the air). For reference, 1000 mph is equal to 447.04 meters per second. So prorate the meters per second for the rough time you were in the air and see how it compares with how much the eath moved for you. Of course - we know for a fact that the ground will not have (nor ever will) move more than zero distance underneath us (presuming no earthquake of course). This also accounts for why an Olympic event such as the long jump, doesn't always have to be in exactly the same direction (and/or various allowances made for different latitudes) relative to the earth's supposed rotation. If the earth were rotating in the way claimed then it would cause all manner of (unfair) variations to the competitor's jump distance. In my estimation, the perception about the reality of this existence (as to it's 'shape') is so obvious that there can only be three possible reasons for claims that it is not a flat plane which we live upon. A person has not overcome beliefs programmed into them. A person is an agent pushing a particular agenda for their 'employer'. A person does not have the requisite intelligence to accurately process such basic observations and perceptions and thus arrive at a result which is accurate. Btw, when traveling in aircraft which fly with no doors on (e.g. like skydiving planes), which quite often go up to 20,000 feet, there is no curvature to be seen on the horizon. Any curvature seen whe looking through a passenger aircraft window, is caused by the slight fish-eye lens type effect of the airplane window, which presumably have the production of such an effect built into their design.