Hypercubic heaven, cubic earth

The sophists are naturally put off by the concept of higher spatial dimensions the same way they are put off by scientific proof of psi phenomena or photographic evidence that there was no communism or equality in the Soviet Union.

More precise than the phrase "round heaven, square earth" would be "hypercubic heaven, cubic earth."  Additionally, heaven is not actually removed from our universe.  That realm of experience is just very distant from our everyday experience the way Nirvana is very distant from our everyday experience.  However, humanity can bring itself closer to those realms of experience through genuine altruism which comprises real civilization.