It may also be worth noting that in order for thought experiments to be valid one requires sufficient understanding of the problem domain. For example, Einstein's Special Theory of Relativity resulted from the fact that Maxwell's equations were not frame-independent. Einstein felt the general form of the equations was valid and sought to find a way to make them frame-independent. Had he not known about and understood the problem with Maxwell's (brilliant) equations, none of Einstein's later work would have been possible.