Self-sacrificial love: evolutionary deception or theological reality?

It has become fashionable in our culture to see science and religion as enemies locked in a conflict that can only end when one of them breathes its last breath. This is ironic since modern science had its origins in the minds of European Christians. Scientists of the 16th-18th centuries, like Copernicus, Galileo, and Newton were Christians who believed that God's revelation takes the form of two books, the written Scriptures and the Book of Nature. In doing science they believed they were studying the handiwork of the Creator. This positive outlook eroded as pessimism about religion grew in response to the Thirty Years War. This devastating war, conducted by kings and princes in the name of the Christian God, led to suspicion about religious claims and philosophical attacks on all aspects of Christian theology during the so-called Age of Enlightenment.

The trend to disparage religious belief that was launched during the Enlightenment has expanded recently in response to numerous cultural and scientific developments. Cynicism about religion is once again on the rise in response to violence perpetrated under the guise of religious goals. To make matters worse, developments in scientific understanding of biological evolution have added fuel to the fires of criticism; if some academics were to have their way religion itself would be tied to the stake and burned. Perhaps the most (in)famous member of this camp is Richard Dawkins, evolutionary biologist at Oxford University. Dawkins has throughout his career interpreted his scientific research as proof that Darwinism eliminates God altogether, so all religious claims are bogus. In his most recent book, The God Delusion, he openly proclaims his agenda: "religious readers who open [the book] will be atheists when they put it down." (2) While not all who accept the scientific validity of evolution go this far, many do see direct and potentially devastating challenges to religious thought.

One issue potentially undermined by science is Christian theology's central doctrine of self-sacrificial (agape) love made known in the Christ Event. Altruistic service to the Other is paradigmatic for Christianity. But when viewed through the lens of science, genuine altruism--self-sacrificial behavior performed at possible risk and without benefit to the actor--is said to be impossible. If we accept the claims of evolutionary biology and psychology, even Jesus' actions were selfish since they were instrumental in furthering God's aims, not ends in themselves. Extending the analysis, religions become deceptive fictions or cultural parasites that once functioned for group survival but are now maladaptive. (3) While scientific theories about the evolution of altruism and human moral behavior need to be taken seriously by theologians, caution is in order. By using anthropomorphic vocabulary for aspects of genetic selection, theorists have made it inevitable that scientific hypotheses about altruism lead us into logical fallacies and confusion. Following an overview of the uses and abuses of the concept in science and theology, I will offer evidence to support my belief that, in spite of it all, altruism remains a robust term for theological reflection.

Altruism in the Evolutionary Sciences

In common parlance, altruism means "devotion to the welfare of others, regard for others, as a principle of action; opposed to egoism or selfishness." (4) It refers to actions which clearly are shaped by motives and have moral implications. But when scientists use the term, they do not mean precisely the same thing. In evolutionary science "altruism" is a metaphor used to describe other-oriented behavior that enhances the fitness/survivability of the recipient at cost in fitness to the actor. Strictly speaking, this is measured in terms of the numbers of copies of genes passed on to the next generation. Individuals increase fitness either directly by passing on their own genes or indirectly by enhancing reproduction of others, so a biologically altruistic act would result in lost or diminished reproduction of the actor's genes. Morality and motivation play no role here.

The origin and persistence of altruism is "one of the enduring puzzles" facing biologists today and it has become the object of extensive research. (5) Strictly speaking, natural selection should eliminate altruistic behavior, but it does not. This problem has led to voluminous literature that offers literally hundreds of theoretical models for altruism in evolutionary biology. Although there is much disagreement on the details, most evolutionary biologists agree that the driving factor in all helping behavior is genetic survival. (6) In this paradigm, altruism is merely genetic selfishness, explained functionally in terms of reciprocity, kinship, or group selection.

Reciprocity, or reciprocal altruism, is a form of barter driven by the assumption is that if one helps another, when roles are reversed, the helping will be returned. In this framework, altruism is a short-term strategy aimed at long-term gain. This is sometimes called "Tit for Tat," and one of the most captivating displays is found in the Costa Rican vampire bat. (7) The vampire bat works hard to survive since it lives by drinking the blood of much larger animals. Very young bats tend fail in the search for blood one out of every three nights, while older bats are unsuccessful about one in ten nights. Feeding must be successful at least once every sixty hours or a bat will starve. Since the bats are nocturnal, failing two consecutive nights would likely mean death. A fascinating form of reciprocal altruism has evolved that increases chances of survival. When a bat feeds effectively, he drinks more blood than he needs, and when he returns to the roost, he regurgitates some of the excess to feed others who have failed. In a purely Darwinian survival-of-the-fittest model this should not happen, especially since in at least some of the observed cases sharing occurred between unrelated bats. Individual bat survival would be enhanced by building up nutritional reserves to tide them over the inevitable nights of failure. But instead the bats engage in this exquisite form of survival insurance that involves a kind of score keeping--"You give to me and I'll give to you. You cheat me, and I'll cheat you." (8) The bats have a relatively long life span (up to twenty years), live in close proximity, and develop individual sharing relationships--bats who have shared blood in the past receive blood when needed from the recipient of past generosity. This remarkable example of reciprocal altruism underscores that the tendency toward cooperation is inherent in nature--survival is dependent upon it.