The Linda Problem

Linda is a single, 31 year old woman who majored in philosophy, and she is very outspoken in her views. During her time as a student, she was profoundly concerned with discrimination and issues of social justice. She also participated in anti-nuclear demonstrations.

Which of these is more likely?

1. Linda is a bank teller.

2. Linda is a bank teller and is active in the feminist movement.

It might surprise you (because you’re smart) that most people asked this question will typically choose the second option.

Amos Tversky and Daniel Kahneman named this phenomenon conjunction fallacy, but it’s just as commonly called “The Linda Problem.” What’s going on here?

First, let’s talk about the logic. When you have two choices, and one choice means X has to happen, and the other means that X has to happen and something else must also happen, the first choice is automatically more likely to happen. This is about as basic as probability gets, and we humans understand this at some level.

So, why do we mak…