Stereotyping overpowers logic: If Linda is a feminist, Jonathan must be gay

Foto von Alina Grubnyak auf Unsplash

Before we get to Jonathan – have you heard about Linda?

Linda is 31 years old, single, outspoken, and very bright. She majored in philosophy. As a student, she was deeply concerned with issues of discrimination and social justice, and also participated in anti-nuclear demonstrations.

Which is more probable?

• Linda is a bank teller.
• Linda is a bank teller and a feminist.

If you’re like 90% of the population, you’d select the second option. But if you’ve taken Psychology 101, chances are you know that the correct answer is option one.

The description of Linda makes it seem obvious that she must be a feminist. She doesn’t sound like a bank teller, but if she’s a bank teller in both option scenarios, she must at least also be a feminist – right? But if we take a moment to think about it, we can see that option two is a subset of option one: if, for example, 5% of people in the world are bank tellers, the percentage of bank tellers who are also feminists must be lower than 5%.

This is Tversky and Kahneman’s lovely illustration of a conjunction fallacy: the probability of two options occurring seems more likely than just one of those options occurring. The mental representations that we have are so strong that they can overwhelm basic probabilistic reasoning.

This has been demonstrated for bank tellers and feminists. But do we have such strong mental representations of groups which are not “chosen” in the same way that people choose a profession or social activism movement? Would a conjunction fallacy also occur for race and sexual orientation categories if strong stereotypes are cued?

Jonathan is a Theatre Arts student in San Francisco. He is atheist, and in his spare time he often goes to the opera.

Which is more probable?

• Jonathan is Black.
• Jonathan is Black and gay.

Preliminary evidence from my recent research suggests that people also tend to commit a conjunction fallacy in this case. The description cuing stereotypes about gay men (which is oppositional to stereotypes about Black men) persuades people that the probability of Jonathan belonging to two categories is greater than the probability of him belonging to just one. This effect was found with both Black and White US American participants – the effect not being moderated by participant race further demonstrates its robustness.

Without the description, people know that it’s less likely that a given individual is both Black and gay, than just Black. In fact, previous research has shown that it’s actually quite difficult for people to imagine that a minority group member may belong to an additional, intersecting minority group (e.g., the intersectional invisibility of Black women). This conjunction fallacy demonstrates the degree to which stereotypes continue to underlie our intuitions and judgments about others. Having some general mental representations of groups is not necessarily bad, and is basically inevitable, but as a society we might be a little too optimistic in thinking that stereotypes no longer inform our day-to-day judgments of others.