The ‘Monty Hall problem’: Logic gone bad

Suppose you’re on a game show, and behind each of three doors is a prize. Behind one is a new car; behind the others, $10 gift cards to some fast food chain. You pick door #1 on a hunch. The host, who knows what’s behind the other doors, opens door #3 to reveal one of the gift cards. “Before I open door #1,” says the host, “would you maybe like to change your choice?”

The question is: Should you?

On the surface, many people would think no. After all, it’s still a random guess; it’s simply between two doors now instead of one, and the chances of getting that car are seemingly 50/50.

Marilyn Vos Savant, Parade magazine columnist and owner of a legendarily high IQ, once put this question to her readers. When she herself advised switching the original choice to door #2, they couldn’t believe her advice. Thousands of readers, including professional mathematicians, wrote in to chastise her on her faulty logic.

But when the problem is broken down, guess what: It turns out you are better off changing your choice. The very understandable assumptions of the masses were incorrect, and many apologies to Vos Savant were forthcoming.

HR Memos D

The “Monty Hall problem” became the subject of essays, papers and even books as an example of supposedly clear truths becoming anything but upon closer inspection.

Look it up online for the brain teaser’s full explanation. Before (and after) you do, consider that real wisdom is often the result of not accepting apparent certainties until they’re put through a rigorous analysis. For some, this mental process takes place in just seconds; for others, it takes a slower, more mindful approach. Most, unfortunately, are nervous about even questioning that which seems unquestionable.