I'm now reading 'Breaking the Spell: Religion as a Natural Phenomenon' by Daniel C. Dennett (Viking, 2006, ISBN 0-670-03472-X). The author also wrote 'Darwin's Dangerous Idea' . This book is a philosopher's attempt to study religion in the light of evolutionary biology.
Chapter One, 'Breaking Which Spell ?' introduces the idea of memes by an analogy to the lancet fluke Dicrocelium dendriticum which has an intermediate stage in ants where it "takes over" the ant's brain and "forces" it to crawl to the highest point of blades of grass in order that the ant may be ingested by ruminants such as cattle or sheep which happen to be the next host of this parasite's life cycle. This worm is very much like the memes which the author will be discussing. They are "selfish" in that there is a struggle for existence amongst memes, and the "fittest" survive.
The author next tries to define what he calls "religion", and he notes some of the problems in arriving at a definition. His tentative definition is, "a social system whose participants avow belief in a supernatural agent or agents whose approval is to be sought". This sort of definition obviously excludes Zen and some other forms of Buddhism, but it does include most Buddhists and even most Daoists. The author opens this chapter with a quote from Freud's 'The Future of an Illusion'. More on this in the next post.