  What is frequently left unclear in discussions of these devices is whether a compensating entropy increase must still take place and if not, what implications this has. To some, most notably Feyerabend, no compensation need occur and the argument is continued to claim explicitly the second law of thermodynamics is unconditionally violated. To others, such as Popper, it indicates that the second law of thermodynamics is only applicable to large systems with many degrees of freedom. The engine is used to demonstrate the domain of validity of thermodynamics, in a similar manner to Maxwell's original demon. From this point of view, the Smoluchowski trapdoor may still be viewed as a thermodynamic system but the Szilard engine is not. Advances in technology, such as in nano-technology and quantum computation, may render this argument problematical, as the ability to construct reliable devices manipulating the states of individual molecules will, if there is not some additional physical constraint, eventually allow the construction of macroscopically large numbers of such devices. If each device could reliably, continuously extract even microscopic amounts of heat, then in aggregate there would again be the production of macroscopically significant quantities of work.