2. The Menger Sponge, p. 162

The book discusses the possibility that the universe is infinite in all directions, that is, in the very small as well as the very large. Superficially, it seems easier to accept an infinitely large universe, as expanding space makes room for more. The diagram of the Menger sponge on page 162 could be considered a symbolic representation of the infinite recesses of inner space. Theoretically, it is a solid with infinite surface area but zero volume!