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Good magicians never reveal their tricks, but Dirk Bernhardt-Walther does. 

The associate professor of psychology in the University of Toronto's Faculty of Arts & Science teaches students about the fallibility of human perception and the mind in his popular first-year foundations course , which focuses on disappearing acts and other magic tricks.  

Dirk Bernhardt-Walther

Magicians exploit human fallibility to wow audiences, Bernhardt-Walther explains – and gaps in people's attention spans and perceptual abilities offer magicians plenty of opportunities to dupe unsuspecting audiences. Humans’ limited contrast perception, for example, enables magicians to hide dark objects against a black background, creating the illusion that they have been conjured from thin air. 

“Magicians also plant false memories. They’ll tell you what you just saw, and you’ll believe it whether it’s true or not,” Bernhardt-Walther says. “Or they’ll ‘force’ a card on you – one you think you’ve chosen of your own free will.”

Magicians can fool even the brightest minds into believing their tricks are real.

“A high working memory capacity may help you to focus better on what the magician is doing, but you’re also more likely to miss something that comes up unexpectedly,” Bernhardt-Walther says.

“Academics are the easiest to fool,” he adds, with a wry smile, “because they concentrate very hard. That makes it easier for the magician to do something on the side that they don’t see.”

As for kids, they are often hard to impress with magic because one of the key requirements is a “strong belief in what’s possible and what’s not,” he says.

“Kids believe in all kinds of things – the Tooth Fairy, Peter Pan, Santa Claus. Even some of our modern technology seems like magic to them. So, for kids, seeing yet another amazing thing happening in their short lives doesn’t always produce the same effect of astonishment that makes stage magic so entertaining for adults.” 

The study of how magic works in the human brain can help psychologists understand the many other ways in which humans are suggestible, Berhardt-Walther says. Whether testifying as an eyewitness to a crime or making a more mundane decision, people often trust their memories. But Bernhardt-Walther's students learn that people can't always rely on their senses. 

“It’s humbling,” says Stella King, a life sciences student and member of Innis College. “One takeaway from this course is that our brains are so unreliable: We feel we’re smart, but we’re not that smart. Our brains are actually quite flawed.”

As an aspiring scientist, King says the course helped her understand why she gets impatient while analyzing processes where the outcome is already known. “Magicians prey on the fact that your brain is always jumping to conclusions,” she says. “Something we’ve learned in terms of neural processing is that your brain is always trying to use the least amount of energy, and the least amount of time, to get to a conclusion.”

Life sciences student Doga Pulat, a member of New College, said the class gave her a better understanding of the workings and development of the human mind. Its many apparent flaws could be “evidence of the complexity of the evolution of the human mind: They’re a gateway into what aspects of perception have been truly necessary for survival, and what aspects can be spared for more efficient processing,” Pulat says.

But it's worth asking: Does revealing magic tricks suck the fun out of watching them?

In response, Bernhardt-Walter makes a physics analogy. “If you know the physics of the refraction of light, do you enjoy rainbows any less? I don’t. I appreciate them more, because I can see how they are made – the angle of the sunlight, the raindrops in the air, the way they come together to create a really nice sight.”

His students appear to agree. “I do not feel that magic has been spoiled for me, quite the opposite really,” Pulat says. 

“Magic will always be entertaining, because it will always be theatrical,” adds King.

A trick that may appear simple after being studied in the classroom still requires the dexterity and stage presence of a magician to fool a crowd of skeptics. 

Indeed, Bernhardt-Walther’s course reveals that magicians are not only expert entertainers, but canny psychologists themselves. “Artists discover how the visual system works by trying things out; scientists draw inspiration from the artists,” he says. “There’s something similar going on with magic. To investigate the human mind, scientists are drawing from a rich bed of techniques already discovered by magicians."