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The berglas effect- How is it done?

  1. Aug 14, 2011 #1
    This is referred to as the "holy grail" of card tricks. I don't think people could figure it out, but it might be fun to try. Here's a youtube video of the trick.

    I was reading some magician's forums, and there were various speculations about it possibly involving trick decks and memorizations. Even so, the trick, as performed, doesn't seem like any of that would help. The most obvious solution would be that there are in fact stooges. But the first example involves British tv personalities. From what I've read, Berglas perfomed the trick for other magicians who were stunned. The man performing the trick is Berglas's best friend, supposedly one of the only other people who knows how its done.

    It's interesting, because by all means, it looks completely impossible. Any thoughts?
    Last edited by a moderator: Sep 25, 2014
  2. jcsd
  3. Aug 14, 2011 #2
    I'd think the person who picks the number is in on it and has the deck memorized. You say "british television personality" as if it is some sort of seal of credibility. :P
  4. Aug 14, 2011 #3
    It's possible, but in this case that would require a British tv show host to do alot of work to help out a magician. Also, since this trick is considered so valuable, you'd think one of the stooges (over the many times it was done) would have offered to sell the secret.

    Anyway, here is an interesting discussion on the trick, recounting several incidents where the trick was performed by Berglas solo for magicians.

  5. Aug 14, 2011 #4
    My basic point as to why the stooge explanation seems unlikely is that it requires a fairly large conspiracy. You need several magicians and others, including celebrities to testify falsely that he has done it for them, you need multiple stooges at mulitple shows, all of whom would have to keep the secret, and who have a lot of incentive to come forward (since there are people offering money to learn the secret.) You also need alot of interested people, including magicians, to not to have been able to sniff it out. It just seems unlikely, although i suppose it is the simplest explanation.
    Last edited: Aug 15, 2011
  6. Aug 14, 2011 #5


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    James Randi could learn it in his sleep and then wake up and do it better before he had his morning coffee.

  7. Aug 15, 2011 #6
    The first thing that I noticed is that he apparently does not shuffle the deck, at least not during his trick. It gives the impression that the order of the cards is somehow important though I am not sure that means that the deck is actually stacked. He maybe hints at the way he does the trick when he tells them in the first example that he got them to make the choices that they did. In both versions he holds up and fans out the cards before setting them down and not touching them again. I am considering the possibility that something he does while fanning the cards suggests the choices which these people make. For instance if one were in such a situation, was just shown some cards, and then suddenly put on the spot and asked to name a card one may simply blurt out one of the cards which they observed only a second ago. He may be able to suggest the number in a similar fashion.
  8. Aug 15, 2011 #7


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    Okay, these are usually "party tricks." I could do a similar one in college. There is always an accomplice. The videos provided are NOT good enough evidence for the card trick itself because there are camera cuts.

    Read the book "Moonwalking with Einstein." Card tricks are a common party trick among memory gurus. They will memorize a deck of cards and have people say a number and recite which card it is.

    My guess is that Berglas has very little to do with the trick. One person indicates a card (or number), then the plant says the corresponding number (or card). The trick is done looooong before any cards are counted out. Throw in a false shuffle and you've got yourself a magic show!
  9. Aug 15, 2011 #8
    If you read the link I provided, there were numerous examples of him performing the trick for magicians with no accomplices at all, i.e., the person the trick is being done for both picks the number and the card. Granted, there's no video of that, but you can find other instances of magicians and celebrities having seen the same thing.

    Nevertheless, ok, we've got the stooge theory. Anything BESIDES that which could produce this effect?
  10. Aug 15, 2011 #9
    That would be pretty impressive, and from what I was reading on various magician forums, this was a popular suggestion as to how its done, and then there are "outs" if the people don't state the right cards that involve sleight of hand. Still, it seems incredible to me that this method would produce consistent enough results and that it would work on professional magicians.

    Also to clarify for anyone who misunderstands me, I am not suggesting this is "genuine magic." It is of course an illusion, it's just a darn good one, and having some familiarity with card tricks and sleight of hand, I find it a fascinating puzzle.
  11. Aug 15, 2011 #10


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    David Blane does a good version of a trick like that by offsetting a single (known) card in the deck and riffling at the right speed. The result is that he tells you to think of only one card, but only one seems to be visible during that time. In the TV version of the trick it is a queen of spades. Also one of the most common cards guessed as "random."

    Try this, I'm giving away one of my great party tricks; the cardless card trick.

    Tell someone (a bit inebriated, perhaps), to think of a card. Any card. Give him or her a second to think. Then say: "...and make it random, don't make it a 2 or an ace or a king or something stupid. Pick something really random." (You've just eliminated 23% of the deck, by the way.)

    They will either immedaitely say "okay, got it." Or think of somethign new. If they think of something new, they are the type to have a "preferred random number." They think they're outsmarting you by picking something obvious (if they think of a new card, it's probably because they were thinking of the ace of spades).

    When they're done, stare at them, and tell them to think of the card really hard. You basically have a 1 in 40 chance of just guessing. Double your chances by saying: "hmm, you're not thinking of it very clearly... you're really thinking of two. I might get this mixed up... hmm, it seems to be red." Judge there response. You might get a hint or you might not.

    In the worst case scenario, tell them you've got two cards, say "it's either the seven of hearts, or the queen of spades." (Don't pick two random cards, actually use THOSE two cards.)

    What you've done is you've made quite a few options available:
    • 7 of hearts
    • 7 of spades
    • queen of hearts
    • queen of spades

    So you've actually quadrupled your chances of guessing. You're ROUGHLY at a 1 in 10 chance at this point. However, most people are so eager for you to be right, then will say something like: "No, but it was the 6 of hearts, holy crap man! That's crazy!"

    And your respond, "well, I knew I was getting a crossed signal there. Have you been drinking?" And everyone laughs it off. If you're totally wrong, just shrug... "oh, well."

    If you're spot on... you are the king of the party. But you MUST refuse to do the trick again. YOU WILL FAIL.
  12. Aug 15, 2011 #11
    I was friends with David Blaine's brother in high school. He showed me some pretty interesting stuff. I've met Blaine a few times, and he is a funny character.
  13. Aug 15, 2011 #12


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    This is easy!

    The chances of a given card coming up at a given location are 1 in 52. So, before the show, he simply thinks of a number and a card and tests it - 51 times in a row. They will all fail. But now the deck is loaded for the next one to be a hit.

  14. Aug 15, 2011 #13


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  15. Aug 15, 2011 #14
    It said the first person wasn't a stooge. How about the second and third folks?
  16. Aug 15, 2011 #15
    The chance of a given card coming up at any given location is 1 in 52. The chance of a given card coming up at a specific location is 1 in 2,704.
  17. Aug 15, 2011 #16


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    OK, for the record, before anyone gets the wrong idea, I was kidding around, however...

    ... he spoke incorrectly. He gave the impression that the chances of a hit are 1-in-52 times 1-in-52.

    That is untrue.

    Yes, but there are 52 ways that could happen.

    See, it's not like participant A must pick card 8 (a 1-in-52 chance) and participant B must pick a Queen of Spades (a 1-in-52 chance).

    No, any spot in the deck works - as long as they get the card right.
    pA picks card 1 - 1-in-52 that it's the Ace of spades (a 1-in-2,704 chance).
    pA picks card 2 - 1-in-52 that it's the 4 of hearts (a 1-in-2,704 chance).
    pA picks card 3 - 1-in-52 that it's the 10 of clubs (a 1-in-2,704 chance).

    i.e there are 52 of 1-in-2,704 chances of getting the right card in the right place. i.e. one in 52.
  18. Aug 15, 2011 #17


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    Easy one:

    Get a deck that has assymetry on the back pattern. Align all the cards. After they randomly pick a card, turn the deck 180 (don't flip it, rotate!) so that the back pattern will be opposite from their card. Let them shuffle (90% of the time they keep the cards aligned).

    Let them look at the cards while you sift through them (hild between you so you can be looking at the backart while they anxiously wait for you to pas their card)

    Pass the card, act like you caught something in their eye, scroll back and say "aha" and give them their card.

    They'll say your trick is reading their eyesmind.
  19. Aug 15, 2011 #18


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    Does this have anything to do with the trick being discussed, or is this a distinct trick?
  20. Aug 16, 2011 #19


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    This is not a trick. It's something anybody can do with a doped deck. I can do the same thing with a shaved deck, without even looking at the deck. These are "tricks" that you can buy anywhere and require zero skill.
  21. Aug 16, 2011 #20
    Ha, i'm gonna try that next time we flip a coin to see who breaks at pool :tongue:
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