The age-old question of how people develop a moral sense has been a topic of debate for centuries. Some believe it is instilled in us by God or religious training, while others argue that moral judgment varies according to the culture in which we were raised. However, evolutionary biologist Mark Hauser asserts that our moral sense is part of our evolutionary inheritance, much like our “language instinct.”

 Hauser draws his conclusions from experiments with nonhuman primates, as well as from the “Moral Sense Test,” an Internet-based assessment tool administered to 150,000 subjects in 120 countries. Hauser argues that the capacity for moral judgment is a universal human trait, “relatively immune” to cultural differences.

 Hauser believes that a key ability in making moral judgments is the capacity to read beneath the surface when observing another creature’s actions. Experiments show that monkeys, apes, and other animals share this ability with humans. It is hypothesized this trait was selected by evolution because being able to perceive another creature’s intentions conferred a survival benefit over animals that could only respond to consequences.

 Another important building block in the evolution of a moral sense is cooperation, which takes three different forms in the animal world. The first is cooperation based on kinship. The second is where both individuals receive some cost, but both benefit. The third and rarest type is reciprocity, where an individual gives something up with the expectation that it will receive benefit in the future. The Golden Rule is a formulation in human terms of this adaptation.

 According to Mark Hauser, responses to the Moral Sense Test indicate the presence of a moral grammar that exists in all of us and that influences the way we make moral judgments. He found no difference in the way religious and nonreligious people responded to the test, nor did he find differences between men and women. However, the Moral Sense Test measures moral decision-making, not behavior. Where religion and culture do make a difference is in how people judge particular situations.

 Overall, Hauser’s argument is that our moral sense is innate and shaped by evolution, rather than solely by cultural and religious factors. While religion and culture may influence our moral judgments in specific situations, the universality of the moral grammar in all humans suggests that our ability to tell right from wrong is deeply ingrained in our nature.