See what I mean socialaztec?
They don't provide any direct evidence of a conspiracy, they mearly assume the conclusion and say "The Earth is flat, therefore there must be a conspiracy."
This reveals a fundamental flaw in the Fe'ers understanding of the nature of hypothesis and proof.
A hypothesis is a statement whose truthfulness is not known, but which -- if it were true -- would explain some set of observations.
The proof of that hypothesis would be some other observation which would be seen if and only if that particular hypothesis were true, and not, say, some other hypothesis which also explains the first observations.
But the problem comes when Fe'ers want to test a hypothesis. You can't use the initial observation as proof of your hypothesis. This is a fallacy -- an example of erroneous thinking -- which logicians call a "circular argument". The notion of a circular argument can be best summed up in the following dialogue from one of the best movies ever made:
Sir Bedevere: Why are you trying to burn that woman?
Villagers: Because she is a witch!
Bedevere: How do you know she is a witch?
Villagers: Well, we wouldn't be trying to burn her if she weren't.
Let's say, for example, that I observed my car windshield was wet. I might hypothesize that it has recently rained. But how would I prove that? If I were like the villagers in the exchange above, I would consider it already proved: The wet windshield proves it rained.
But the wet windshield was the observation I was trying to explain.
To know whether or not it rained I would need to look for other signs of recent rain. For example, I could look at the sky and see if it's cloudy. Or I could see if the distant surroundings were also wet. Or I could ask somebody who may have witnessed the rain.
I have to do that because there are lots of other hypotheses.
With the circular argument I can put each of these hypotheses into a syllogism and say,
My windshield is wet, therefore it has rained.
My windshield is wet, therefore moisture has leached out of the glass.
My windshield is wet, therefore a sprinkler has sprayed my car.
All three of these seem reasonable, but they all can't be correct. I can be absurd and hypothesize that my windshield is wet because space aliens are spying on me and put that moisture there to absorb my brainwave patterns.
The resulting "proof" would be:
My windshield is wet, therefore aliens are spying on my brainwave patterns.
Yes, that's supposed to sound absurd. It's supposed to show that a pattern of reasoning which can produce such absurd conclusions isn't a valid pattern of reasoning. Circular arguments are "tautological" meaning that they're always true. They're true not because they arrive at a good conclusion, they're true because they're structured to be true no matter what conclusion or premise is involved. That's why they aren't useful for proving anything.
Let's do an example that involves FE arguments.
FE'ers observe that in photographs from supposedly orbiting spacecraft, there are flaws which seem to indicate that the photo is faked or modified. They hypothesize that the photos were produced by NASA with image rendering software. This hypothesis, if true, would explain the observation.
But how to go about proving it? Unfortunately most FEer's simply use the circular argument. When asked to provide evidence that a photo is faked, they point back to the errors and say, "See? The errors are there, therefore they were created in the lab."
But reasonable people are not convinced by the tautological argument, nor should they be. When we say there is no evidence for the existence of a government FE conspiracy, we mean that there is no evidence which undeniably and unquestionably shows that the conspiracy exists. The FE'ers need to provide secondary, unambiguous evidence that could only be explained by their hypothesis. For example, they could try to find increased activity at government-funded photo labs. They could try to document the purchase of equipment and supplies by NASA that would only be useful to a photo lab that was falsifying pictures. They could even try to find some of the people who participated in this alleged cover up of the shape of the Earth.