You should have multiple independent types of observation. If you only know about the metal tube idea from flying in one yourself, it might have been a simulati

You should have multiple independent types of observation. If you only know about the metal tube idea from flying in one yourself, it might have been a simulation. You should have other facts that also support the same conclusion (eg. knowledge of aerodynamics, people quickly moving around the world, etc.) so that it would be hard for them all to be wrong in the same way. You don't have to witness it with your own eyes because, again, it would be hard for them all to create the same consistent lie from multiple perspectives even if they were conspiring.