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Undo Influence Principle by Simon Aronson

Created by: Simon Aronson

The Undo Influence Principle by Simon Aronson is a self-working card trick that has been used to fool even seasoned magicians like Penn and Teller. It involves two participants choosing cards, returning them to the deck, and then revealing that two prediction cards in the deck correctly indicate the positions of the chosen cards. This trick is a great example of close-up card magic that requires no memorized deck, making it accessible to magicians at all skill levels.

Key features

  • Self-working principle, no complex sleight of hand required

  • Can be performed with any deck of cards

  • Fooled Penn and Teller, indicating its high level of deception

  • Multiple applications and routines provided by the creator

  • Suitable for close-up performances

Pros

  • Highly deceptive and fooling

  • Easy to learn and perform

  • Versatile with multiple routines possible

  • No need for a memorized deck

Cons

  • May require some practice to present convincingly

  • Limited to card magic enthusiasts

Effect

The Undo Influence Principle by Simon Aronson is a deceptive card trick that leaves audiences baffled. The effect involves two participants freely selecting cards from a shuffled deck. After the cards are returned and the deck is mixed, the magician reveals two prediction cards that accurately indicate the exact positions of the chosen cards in the deck. The trick appears self-working, with no suspicious moves or sleight of hand, making it highly convincing.

Full Details

The Undo Influence Principle is a clever method that relies on a subtle yet powerful principle rather than complex sleights. Simon Aronson provides multiple applications of this principle, some involving a memorized deck and others that are entirely self-working. The basic version, found in Try the Impossible, allows for a straightforward performance with minimal setup.

The trick progresses naturally:

  • Two participants each freely select a card.
  • The cards are returned to the deck and lost in the shuffle.
  • The magician reveals two prediction cards that correctly identify the positions of the chosen cards.

The method is so deceptive that it has fooled even seasoned magicians like Penn & Teller.

Who Should Consider the Trick

This trick is ideal for:

  • Intermediate to advanced magicians who appreciate strong, method-driven magic.
  • Performers who enjoy self-working or semi-automatic tricks that require minimal sleight of hand.
  • Mentalism enthusiasts, as the effect can be framed as a demonstration of psychological influence.
  • Those looking for a reliable, repeatable trick that plays well in both casual and formal settings.

Difficulty

The Undo Influence Principle is rated as easy to moderate in difficulty. The basic version is self-working, making it accessible to beginners who can follow instructions carefully. More advanced applications may require familiarity with memorized deck work, but the foundational routine is straightforward.

What Magicians Say

EruditeMagic, in their review of hidden gems from out-of-print books, highlights the Undo Influence Principle as a standout effect:

"Simon Aronson's principle is devious and has been used to fool Penn & Teller. It's effectively self-working, and every time you do it, you'll marvel that it actually works."

The trick is praised for its deceptive simplicity and strong impact, making it a valuable addition to any magician's repertoire.

If you're looking for a card trick that combines fooling methodology with minimal effort, the Undo Influence Principle is a must-learn.

What people are saying about Undo Influence Principle

EruditeMagic says...

The Undo Influence Principle is a self-working principle demonstrated with a card trick that fooled Penn and Teller. [...] It's effectively a self-working principle Simon gives you a lot of different applications some more difficult and involving a m deck than others but the basic one which you can find in his try the impossible lets you have two participants choose cards return them to the deck you have two prediction cards that were in the deck that indicate the positions of the two Chosen and returned cards and it's absolutely correct.

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