How do magicians know what card you're thinking of?

Wanna see a magic trick? Name a playing card out loud. Go ahead, we won't hear you. Now here's the trick: it turns out over 50% of people, when asked to name one card in a 52-card deck, choose one of only four cards.

Which card did you choose?

According to newly published research by psychologist (and magician) Jay Olson, if you're like most people, you selected between the Ace of Spades, the Queen of Hearts, the Ace of Hearts, or King of Hearts. Here's the exact breakdown:

Ace of Spades - 25%
Queen of Hearts - 14%
Ace of Hearts - 6%
King of Hearts - 6%

You can find a list of cards and their selection frequencies on Olson's website. (For those of you too lazy to look it up on your own, only 2.13% of people choose the Queen of Diamonds when they're asked to name a card. Poor Gob.)

So why do people tend to gravitate toward these cards? That's something Olson is trying to figure out, in part because it "can shed light on the perception of ordinary objects," but also because it can "help us understand why magic works in the mind."

For instance, Olson found that the way you pose a question during a card trick (sorry, card illusion) can have a significant effect on its outcome. Over at Scientific American, Olson explains that while asking people to name a card gives rise to one set of selection frequencies (the four most frequently chosen cards being the ones listed above), asking someone to visualize a card actually gives a different result:

When asked to visualize a card, people seemed to choose the Ace of Hearts more often. In our sample, they chose it almost twice as often when asked to visualize (11%) rather than name (6%) a card. Perhaps something about the visualization process makes people more likely to think of this particular card.

Systematic studies such as these can help form the basis of a psychology of card magic. Magicians can improve their tricks by knowing which cards people like the best or choose the most. Meanwhile, psychologists can follow up on unexpected findings to understand why people may misreport seeing red Sixes or why the wording of a question may bring different cards to mind.

And this is only the beginning. Applying these results, we can uncover the mechanisms behind the principles of card magic. If magicians can influence the audience's decisions, what factors enable this influence? Why do people still feel like they have a free choice?

Check out the rest of Olson's SciAm piece for more details on the surprising results of his study.

Image by Suslik1983 via Shutterstock