Here come those arrogant statements you requested
There are plenty of field tests that can be done by us here on the ground without going into space...someone earlier mentioned watching ships sink below the horizon
It's funny that you take issue with people regurgitating things from science books, but you seemingly have nothing to say about people regurgitating things from the Flat Earth Society
The notion that a statement can't be accurate without first hand experience is absurd...I am POSITIVE you believe in plenty of things of which you have no first hand experience