The puzzlement consists of using &quot;universe&quot; in two incompatible contexts without paying clear attention to the distinction between the contexts.<p>The first context is the ordinary one in which the universe is roughly the container for everything that is including ourselves.<p>The other context is one in which the universe is a simulation of a container for everything that is including ourselves that is indistinguishable by us from an actual container for everything that is including ourselves.<p>It&#x27;s fine to use the latter definition, so long as one recognizes that the use is very odd and problematic and any conclusions one draws while using it are simulated conclusions about the simulated container and not conclusions about the actual container for everything that is including ourselves. To put it another way, if the universe is a simulation then &quot;light&quot; and &quot;speed&quot; and &quot;C&quot; refer to elements of the simulation and need not have a one to one  correspondence to entities in the actual universe. Human knowledge can only be knowledge of the simulation.<p>Our knowledge is limited to things it is possible for humans to know. If we&#x27;re in a simulated universe, then we can only know about the simulation.