A bias is a tendency, inclination, or prejudice toward or against something or someone. Some biases are positive and helpful—like choosing to only eat foods that are considered healthy, or staying away from someone who has knowingly caused harm. But biases are often based on stereotypes, rather than actual knowledge of an individual or circumstance. Whether positive or negative, such cognitive shortcuts can result in prejudgments that lead to rash decisions or discriminatory practices.
The most common examples of unfair bias are based on stereotypes about another person's race, ethnicity, gender, religion, or sexuality. This type of bias can have harmful real-world outcomes, and can also increase susceptibility to “stereotype threat,” the phenomenon in which people behave in certain ways to avoid confirming a common stereotype about their own particular group.
Even people who are not deliberately prejudicial may have what’s known as implicit biases, or biases formed from lifelong societal input that escape conscious detection. Paying attention to helpful biases—while keeping negative, prejudicial, or accidental biases in check—requires a delicate balance between self-protection and empathy for others.