Evolutionary psychology of religion

Although evolutionists had previously sought to understand and explain religion in terms of a cultural attribute which might conceivably confer biological advantages to its adherents, Richard Dawkins called for a re-analysis of religion in terms of the evolution of self-replicating ideas apart from any resulting biological advantages they might bestow. He argued that the role of key replicator in cultural evolution belongs not to genes, but to memes replicating thought from person to person by means of imitation. These replicators respond to selective pressures that may or may not affect biological reproduction or survival.
In her book, The Meme Machine, Susan Blackmore regards religions as particularly tenacious memes. Many of the features common to the most widely practiced religions provide built-in advantages in an evolutionary context, she writes. For example, religions that preach of the value of faith-based belief over evidence from everyday experience or reason inoculate societies against many of the most basic tools people commonly use to evaluate their ideas. By linking altruism with religious affiliation, religious memes can proliferate more quickly because people perceive that they can reap societal as well as personal rewards. The longevity of religious memes improves with their documentation in revered religious texts.
Aaron Lynch attributed the robustness of religious memes in human culture to the fact that they incorporate multiple modes of meme transmission. Religious memes pass down the generations from parent to child and across a single generation through proselytism. Most will hold the religion taught them by their parents throughout their life. Many religions feature adversarial elements, punishing apostasy, for instance, or demonizing infidels. In Thought Contagion Lynch identifies the memes of transmission in Christianity as especially powerful in scope. Believers view the conversion of non-believers both as a religious duty and as an act of altruism. The promise of eternity in heaven to believers or hell to non-believers provides a strong incentive to accept and retain Christian faith. Lynch asserts that belief in the crucifixion in Christianity amplifies each of its other replication advantages through the indebtedness believers have to their Savior for sacrifice on the cross. The image of the crucifixion recurs in religious sacraments, and the proliferation of symbols of the cross (itself a meme) in homes and churches potently reinforces the wide array of Christian memes.