Fooling Garwulf"Where There's Smoke, There's Magic" ...and Hacking the BrainFooling Garwulf - RSS 2.0
Likewise, if I do a rising card trick - as I hold the deck, I tap it three times, and on the third tap a card appears to rise from the middle - the number of taps is very important. What I'm doing is showing you the entirety of my hand twice, so that you'll see what all of my fingers are doing. The third time, when my hand is obscured by the rising card, your brain will assume that my fingers are doing the same things they were on the previous two taps - and, of course, they aren't.
Another side-effect of the assumptions that our brains make is called "change blindness."
Because our brains only take note of important details, and then build our perception of reality around them, the lack of any stimulus to prompt the brain to re-examine what it sees can leave very real changes unnoticed. The reason is simple - having noted a detail such as a deck of cards on the table, without a reason to doubt that it is the same object, the brain just assumes that it will be the same deck of cards the next time it enters your vision. If, while you were looking at something else on the table, somebody was to quietly replace it with a different deck of cards, or add another deck of cards beside it, you would be unlikely to notice the change.
This is an important survival mechanism - our brains cannot operate fast enough for us to function if it has to re-evaluate every single thing it sees every time it sees it. However, for a magician, this is a Godsend. It doesn't take much misdirection to draw your attention away from a deck of cards long enough to perform a sleight - but since there is nothing to suggest to your brain that it needs to re-evaluate that deck of cards, it will assume that the deck is in the same state it was the last time you saw it.
Much of this is advanced and experimental psychology, and it is only in recent years that psychologists have begun to recognize just how far ahead of the curve magicians have been for so very long. After all, in the end the magician's best ally is not the sleight or the prop, but the human brain and the many assumptions it makes.
Author's Note: Since this is a feature about magic, we must ask for discretion when it comes to discussing methods in the forums. For the sake of preserving the mystery for those who do not want to know how the tricks are done, as well as to avoid accidentally exposing the hard work of some very talented magicians, please avoid revealing methods in the discussion threads. If you must talk about a method in a way that might expose it, please use spoiler tags.
Robert B. Marks is the author of the new and revived Garwulf's Corner on The Escapist, as well as Diablo: Demonsbane, The EverQuest Companion, the original Garwulf's Corner, and the co-author of A Funny Thing Happened on the Way to the Agora. His current fiction project is The Eternity Quartet, with Ed Greenwood. His Livejournal can be found here, and he is now on Facebook. He can be reached by email at garwulf at escapistmag.com.