It’s a term that’s still too useful to abandon. Social psychologists have mounds of research on the role that emotions like fear and repugnance play in distorting our assessments of reality—that is, in creating bias. For starters, they’ve found that conscious reasoning is a much newer human capacity—evolutionarily—than gut feeling, and that the brain often deploys reasoned thought to rationalize feelings we already have. Rather than justifying a position—like, say, opposing gay marriage—based on how we actually feel, we often dream up non-existent dangers. Indeed, scientists have shown that our brains developed fight-or-flight mechanisms to help us avoid danger before our rational, deliberative machinery even perceives the threat.

Interestingly, researchers at Cornell and Yale (including Atlantic contributor Paul Bloom) have also shown that conservatives, on average, experience stronger levels of disgust than liberals do, and that an overall sensitivity to disgust correlates with anti-gay sentiment. “Our data show that disgust and politics are linked most strongly for issues of purity, such as towards homosexuality,” the authors explain.

Even more strikingly, researchers have found that people with negative views of gay people are prone to overstate the risks that gay rights pose. In one study, psychologists at Berkeley and Carnegie Mellon University measured subjects’ emotional dispositions and their risk preferences, giving them separate scores for each. When the two sets of variables were correlated, they found that “fearful people expressed pessimistic risk estimates and risk-averse choices.”

It’s no surprise that fearful people would be risk-averse. But this research showed not just that such people avoid risk but that they exaggerate it—in consistent and predictable ways. Researchers concluded that certain emotions, such as fear, activate “a predisposition to appraise future events in line with” whatever the person dreaded to begin with. In other words, fear makes people lose perspective on what the odds of danger really are. These visceral feelings often bypass consciousness, so we’re not even aware of what we’re feeling.

The psychologist Jonathan Haidt describes the amusing rationalizations his research subjects often came up with to justify moralistic positions. For instance, Haidt asked subjects if it was morally wrong to shred a flag while in your home and flush the pieces down the toilet. Those who said it was wrong couldn’t readily explain why. When pressed, one said the flag could clog the toilet.

To take a more common example, people generally disapprove of consensual sex between adult siblings but they can’t say why it’s wrong. Psychologists refer to such feelings as “moral intuitions”—unconscious judgments that stem from emotional responses or learned associations, and are often related to disgust. Haidt says people consult their feelings to help them decide what to believe. This sounds fair enough at first blush, but we’re not just talking about values here. Moral intuitions change the way people see the world around them. When your perceptions of reality are refracted through strong feelings, that’s a recipe for bias. It explains the “harms” arguments about gay rights, and why they persist even though there’s no factual information to back them up.