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Our moral judgments are sometimes guided by the feeling of disgust. When we hear about incest, for example, we know that it’s “just wrong.” This is in part because we feel grossed out by it.

Disgust, according to Cornell psychology professor David Pizzaro, “makes wrong things seem even more wrong.”

But other researchers have argued that disgust doesn’t influence our moral judgments very much. Some claim, “In the context of moral transgressions, participants appear to interpret and use the term “disgust” in a similar way to that of “ ” or “outrage.” In other words, people might see a moral violation and then experience a powerful emotion. They then describe it as “disgust” when something like “anger” would be more suitable.

Moreover, research has found that people are comfortable saying disgust can co-exist alongside moral approval (if you’re grossed out by something a person does, you might not say it’s wrong).

But people are less comfortable saying anger can co-exist alongside moral approval (if you see someone do something that angers you, there’s a good chance you’ll say it’s wrong).

In a new study to be published in the Journal of and Social Psychology titled “The Physiological Basis of Psychological Disgust and Moral Judgments,” Jessica Tracy and her colleagues found that inhibiting disgust reduces disapproval for certain kinds of moral transgressions.

How did they curb disgust in people? Ginger. Ginger is an antiemetic, which means it is a drug that relieves nausea. People take ginger when they are feeling nauseated (not “nauseous”! “Nauseous” means something elicits nausea. Rotting meat is “nauseous.” Smelling it makes people feel “nauseated”).

Professor Tracy and her colleagues hypothesized that ginger might influence people’s moral responses. If disgust influences moral judgments, then maybe manipulating disgust would influence moral judgments.

The researchers ran a series of studies. In one study, they divided participants into 2 groups. One group ingested 3 sugar pills. Another group ingested 3 ginger pills.

The study was double-blind. This means the researcher administering the pills had no knowledge of whether they were administering sugar pills or ginger pills. And the participants themselves didn’t know whether they were ingesting sugar or ginger.

After 40 minutes passed, which allowed the ginger to take effect, participants viewed some disgusting images. They rated the images on a scale from 1 (not at all disgusted) to 7 (very disgusted).

Some images were highly disgusting (vomit in a toilet) while others were moderately disgusting (a man sneezing out particles). For the highly disgusting images, ginger had no effect. The ginger group and sugar group reported similar disgust ratings.

But individuals who had consumed ginger rated moderately disgusting images as less disgusting compared to those who had taken a .

In a different experiment, researchers showed participants moral stories. Participants read moderately severe scenarios such as, “A man who is not in a orders an inflatable doll that looks like his secretary. How wrong is this?”

People who consumed ginger expressed less disapproval and disgust than those who had taken a placebo.

But then people read highly severe cases, such as, “Frank’s dog was killed by a car in front of his house. Frank had heard that in China people occasionally eat dog meat, and he was curious what it tasted like. So he cut up the body and cooked it and ate it for dinner.”

Ginger had no effect on moral judgment here. It appears that ginger reduces disgust for moderate scenarios, but not severe ones.

And the effect of ginger didn’t carry over for other kinds of moral violations. It only worked for disgust. For example, people who consumed ginger were just as likely to say it is wrong to an exam.

Inhibiting disgust reduced people’s disapproval to moderately severe moral scenarios involving disgust. But inhibiting disgust didn’t reduce people’s disapproval of other kinds of moral violations like .

This suggests that when people say they are disgusted by certain kinds of moral violations, they might be using “disgust” as a synonym for “anger.”

As the researchers put it,

“When people say they are disgusted by the infliction of harm to others, unfair treatment of different people or groups, demonstrations of disloyalty, or disrespect for an authority figure, they may be using that word metaphorically; based on the present results, these kinds of violations do not elicit actual disgust feelings. This conclusion is consistent with prior studies showing that for violations outside the purity domain, reports of disgust tend to be highly correlated with reports of anger—suggesting that in these contexts reported disgust may reflect a more general outrage.”

In short, ginger is known to inhibit nausea. This study suggests ginger also interferes with moral disgust—up to a point. The researchers argue that when we feel physiological disgust, it tells us that something morally wrong has happened. But if this disgust response is dampened, people become less morally judgmental.

But for moral violations that don’t involve disgust, people’s judgments don’t change when they consume ginger. And when people say they are “disgusted” by something, they might actually mean “this angers me.”