On the face of it, this might seem strange. Why would having an opportunity to act morally in one setting influence your level of moral outrage in another — especially when your identity is secret the entire time?

Our data support the following explanation: People have a subconscious desire to signal their virtue. Even in private, people implicitly ask themselves, “If I were being observed, how good would I look?”

Consider the participants who were given an opportunity to act morally by sharing money. If they had been observed, their choice would have served as a powerful signal of their virtue (or lack thereof). And as a result, the value of expressing outrage as a virtue signal would decline. After all, if a participant chose to share, she would look virtuous regardless of how much outrage she subsequently expressed toward the selfish person. (And if she chose not to share, she would look dishonorable regardless of how much outrage she later expressed.)

In contrast, the participants who were not given the opportunity to share money had no way to signal their virtue to a hypothetical observer besides getting outraged. So, even though no one was watching, they had a stronger subconscious motivation to express outrage — and, as we found, they reported feeling significantly more outraged.

What our findings show is that asking whether outrage is “pure” is the wrong question. Even authentic outrage is influenced by implicit strategic calculations. This shouldn’t come as a surprise to anyone familiar with evolutionary theories that hypothesize that morality arose precisely as a way of signaling one’s trustworthiness in cooperative endeavors.

But this also shouldn’t strike you as cynical. In fact, we view our findings optimistically. They suggest that if an individual is motivated by a desire to signal her virtue, that does not necessarily mean she is faking her outrage. Of course, people do sometimes fake or exaggerate their outrage to look good. Our point is that the presence of strategic motives does not itself make a moral reaction inauthentic.

That’s something to keep in mind the next time you are tempted to dismiss something as mere virtue signaling.

Jillian Jordan is a postdoctoral fellow at the Kellogg School of Management at Northwestern. David Rand is an associate professor at the Sloan School of Management and the department of brain and cognitive sciences at the Massachusetts Institute of Technology.

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