When it comes to ethical dilemmas, men are typically more willing to accept harmful actions for the sake of the greater good than women. Why is that?

The classic example is traveling back in time to kill Adolf Hitler as a child - the child had not yet done anything wrong but he is going to be responsible for nearly as many deaths as Stalin and Mao, over 10 million people, so wouldn't it be better to eliminated him, or all three of them? A more topical example is the terrorist attacks in France and across the mid-east. Would it be better to torture a terrorist to find hidden explosives that could kill many people at a local café?

Women would be less likely to support the killing of a young Hitler or torturing a terrorist, even if doing so would ultimately save more lives.

According to social psychologists, gender difference in moral decisions is caused by stronger emotional aversion to harmful action among women. Their reanalysis found no evidence for gender differences in the rational evaluation of the outcomes of harmful actions. 

The reanalysis of data from 6,100 participants was done by Rebecca Friesdorf, a graduate student in social psychology at Wilfrid Laurier University in Canada, Paul Conway, Ph.D., a postdoctoral fellow in psychology at the University of Cologne, and Bertram Gawronski, Ph.D., a psychology professor at the University of Texas at Austin, to examine gender differences in judgments about moral dilemmas. Participants had been asked 20 questions that posed various moral dilemmas, including decisions about murder, torture, lying, abortion, and animal research. 

"Women are more likely to have a gut-level negative reaction to causing harm to an individual, while men experience less emotional responses to doing harm," says Friesdorf. The finding runs contrary to the common stereotype that women being more emotional means that they are also less rational, Friesdorf says. 

The reanalysis examined two contrasting philosophical principles that relate to ethics. In deontology, the morality of an action depends on its consistency with a moral norm. Immanuel Kant, the 18th century philosopher who was the most famous proponent of the theory, once argued that it was always wrong to lie, even if a murderer asked whether his intended victim was inside a house so he could kill him. Conversely, utilitarianism holds that an action is moral if it maximizes utility, or the greatest good for the most people. From a utilitarian view, an action could be ethical in one situation and unethical in another depending on the potential outcome. 

Using an advanced statistical procedure to quantify the strength of deontological and utilitarian inclinations, the research team found that women were more likely than men to adhere to deontological principles. However, the researchers found no evidence for gender differences in utilitarian reasoning. The findings suggest that women have a stronger emotional aversion to causing harm than men. However, men and women engage in similar levels of rational thinking about the outcomes of harmful action.

The findings are in line with previous research showing that women are more empathetic to the feelings of other people than men, whereas gender differences in cognitive abilities tend to be small or nonexistent, Friesdorf says.

 Published in the Personality and Social Psychology Bulletin on April 3, 2015.