Imagine somebody asking you to forego much of what makes life pleasurable, such as Earthly love, sex and wealth, in return for a reward that won't be offered until after you die? Religion has managed to do just that to many.

Religiousness constitutes a deep mystery. Because of it, otherwise rational people believe in completely implausible explanations that have no empirical support, give their life for causes that do not benefit them or their descendants. In the name of religion, civilizations have been exterminated and millions have died. How has an apparent affliction like this evolved to affect the majority of humankind?

Religiousness is deeply ingrained. Even when it has been temporarily banned, such as in the former Soviet Union, it reappeared rapidly after the fall of the Soviet Union.

I argue that religiousness is not the product of biological evolution, for it is maldaptive for the individual, but rather the product of cultural selection, which operates on a much faster scale than biological one. 

Humans (and perhaps to a lesser extent, other social animals) evolved the ability to believe what is communicated to them by others even in the absence of direct evidence, and this is clearly adaptive and essential to social behavior.

This "ability to believe", baptized faith, is used by religions around the world. 

In a social species where survival depends on the power of communities to act together, cohesiveness is essential to a community's success. Religion aids this cohesiveness by getting everybody to agree on some fundamentals of the society rather than allowing variability that would ensue from letting each person reason about them. In particular, some of the most successful world religions contain elements in their faith that specifically contribute to propagate the faith: from the value of converting others in Catholicism, to the prohibition of abortion and contraception that results in larger numbers of children and thus of the faithful, to the prohibition to marry outside the faith, risking losing some faithful. Thus, religious communities grow over time, and religious cultures are more likely to survive than non-religious ones.

My friend Ari Hershowitz suggested an interesting idea: that religion may also have an adaptive value in preserving lessons that may occur infrequently enough (once every few generations) that observation and reason alone do not suffice to teach. But these lessons seem infrequent enough that this adaptive value may not be all that much, and there are more rational ways to pass on the lessons of the past than religion.

Note that there are other ways to fulfill the cohesive purpose of religion than what we typically call religious faith, with national patriotism being the most prominent among them. For our purposes here, patriotism is another form of religion. Thus, nations with strong patriotic values, such as China and the former Soviet Union, managed to thrive in the absence of traditional religion. 

Alex Backer, January 4, 2008

P.S. It is interesting to note that some team sports, such as soccer, exhibit the same properties mentioned above. Indeed, the same countries consistently win the soccer World Cup, and it is countries with a deep sense of national pride --Brazil, Argentina, Germany, Italy. It is noteworthy that a country with a deep soccer culture such as Spain, where soccer is so popular that players command the highest salaries in the world and where the world's best players play, but where there is little patriotic tradition --Spain was ravaged by a civil war in the 20th century and is still affected by strong secessionist movements from Catalonia and the Basque nation--, has never reached a World Cup final.

P.S. 2. Of course, the values of many religions, such as 'Do unto others as you would like done unto yourself', can be helpful in many other ways, but there are ways to arrive at those without blind religious faith --anywhere from belief that such a social contract is good for society, to the happiness that comes from helping others or seeing them happy, to respect of the law for fear of the consequences of breaking it.