Sifting through the dirt near Nag Hammadi, south of Cairo, in 1945, a camel driver found the large jar, sealed and buried in time of persecution in the 4th century, which contained the largest collection of ancient Gnostic literature so far available. By 1960 some of the documents had surfaced into the scholarly world and been transcribed. Books and articles gave the non-scholar some sense of the significance of the find (cf. The Gospel Of Thomas by R.M. Grants and others). Now that transcription and translation is complete, Mr. Dart, a Los Angeles Times man with good access to the experts, can offer the layman an overall picture. He is at his best with the story of the efforts by French and American scholars to make sure that they had seen all the find, and to secure money to buy documents or to have them properly photographed and studied. Gnosticism is described as part of the context cf thought out of which the modern world emerged, and as the religion that best expresses the defeatism and despair of the first centuries of the Christian era. (The 'laughter' of the title is more accurately 'mockery'). The light the documents throw on the figure of Jesus, and the movement's connections with Judaism are also discussed in this short book on a topic which may not be beguiling but which is important.