Once I came across a story that shows how easily even scientists can be mistaken. In September 1990, Marilyn vos Savant — a woman with an IQ of 228, listed in the Guinness Book of World Records — answered a reader's question in Parade magazine. The question concerned the famous Monty Hall problem, a probabilistic puzzle inspired by the game show Let's Make a Deal.

The scenario is simple: a participant sees three doors. Behind one is a car, behind the other two are goats. After choosing a door, the host — who knows where the car is — opens one of the remaining doors to reveal a goat. Now the participant must decide: stick with their original choice or switch to the last unopened door?

vos Savant's answer was brief and firm: always switch. Her logic? Switching increases the chances from one-third to two-thirds.

And that’s where the storm began. Marilyn received over ten thousand letters. Nearly a thousand came from people with doctorates. Ninety percent of them claimed she was wrong. The words were harsh: "You completely misunderstand probability," "This is the biggest blunder I've seen," and some even suggested that perhaps women simply can't do math.

But vos Savant was right. Here's why: when you first choose a door, you have a one-third chance of the car and a two-thirds chance of a goat. The host always reveals a goat. If you initially picked a goat — which has a two-thirds chance — switching guarantees a win. If you initially picked the car — which has a one-third chance — switching results in a loss. Math clearly states: switching wins in two out of three scenarios.

Then came the evidence. MIT conducted computer simulations. Thousands of trials. Always the same result: two-thirds. The popular show Mythbusters verified this experimentally. Even the academic community, which initially attacked her, had to admit their mistake.

Why does intuition fail us? People think that after one door is opened, the chance is fifty-fifty. They ignore the original probabilities. They see the second choice as a new event, not a continuation of the first. This is a reset error — our brains like simplicity.

vos Savant's story teaches something important. A woman who read all twenty-four volumes of the Encyclopaedia Britannica before turning ten had to face not only mathematical doubts but also sexism. Yet she stuck to logic. Ultimately, millions of people were mistaken, and she was right.

It's a lesson about the power of mathematics over intuition. About how we might be more biased than we think. And that sometimes it takes courage to tell the truth, even when the whole world says you're wrong.