Imagine?
What do you mean imagine? Is your imagination empirical evidence? A thought experiment where you set the rules to be so that earth is round, isn't much of a though experiment.
Imagine Mars is full of little green men. Now tell me that there is no life on Mars.
I LOL'ed with your Mars example. Not in a way that is mocking, mind you, but in a honest way that appreciates the point you are making.
I think it is well stated.
Any positive claim has a burden of proof. If I want to claim the Earth is round, then I have a burden to prove it. If I want to claim the Earth is flat, then I have a burden to prove that. The evidence must then be in proportion to the size of the claim. What I mean is this: suppose I told you that my name is David. You will probably believe that without much evidence. David is a known name, and many folks are named this. You may not bet you LIFE on it being true...but you might take my word for it. Suppose, however, that I say my name is Qjksoauhjfrtpa9ehfszEADKLUhfawkdf. THAT is a bit of a bigger claim! You might ask for some ID before you believed it!
So, I guess the point I am making is that it isn't fair. FEers have a harder job than REers, because FEers have a bigger claim -- they must content with an entire field of experimentally proven evidence which validates RET. Hence, FEers in fact have a higher burden of proof needed to support the larger claim. That is not easy on you all, and I am beginning to realize that and cultivate compassion for it.
Please do let me know if I might help.