Heaven is constantly shifting shape because it is a history of subconscious human longings. Show me your heaven, and I'll show you what's lacking in your life. The desert-dwellers who wrote the Bible and the Quran lived in thirst--so their heavens were forever running with rivers and fountains and springs. African-American slaves believed they were headed for a heaven where "the first would be last, and the last would be first"--so they would be the free men dominating white slaves. Today's Islamist suicide-bombers live in a society starved of sex, so their heaven is a 72-virgin gang-bang.