Self-working magic

The term "self-working" has come into common usage in the world of magic as a reference to tricks that do not require sleight of hand or secret moves.

[1] Strictly speaking no magic is "self-working", since tricks still need to be performed and presented correctly, and so some writers prefer the term "auto-magic", which was popularized by Michael Breggar in his monthly "Auto-Magic" column in The Linking Ring.

[2] Many self-working card tricks rely on mathematical principles, and can be replicated by following the steps correctly.

A simple example is the trick "Magical 13", where a deck of playing cards is secretly set up with all the suits in order.

Some consider optical illusions and some science demonstrations, where the wonder comes from unexpectedness of a natural phenomenon, to fall into the category of self-working magic as well.

The illusionist sums the first number on each card on which the target number appears. In the SVG file, click a card to toggle it.
Explanation of the Piano Trick:
  1. Cards are put in pairs, except for the last card, between the spectator's fingers and thumbs.
  2. The cards are gathered into two piles.
  3. The illusionist pretends to magically move the single card to the smaller pile.
  4. The smaller pile is shown to have three pairs and a single card.