555: Two Mirrors

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Two Mirrors
If you actually do this, what really happens is Douglas Hofstadter appears and talks to you for eight hours about strange loops.
Title text: If you actually do this, what really happens is Douglas Hofstadter appears and talks to you for eight hours about strange loops.


In folk lore, Bloody Mary is a legendary ghost or spirit conjured to reveal the future. She is said to appear in a mirror when her name is called multiple times. The Bloody Mary apparition may be benign or malevolent, depending on historic variations of the legend. The Bloody Mary appearances are mostly "witnessed" in teenage group participation games, often as part of a game of truth or dare.

In this xkcd comic, Megan sets up two mirrors facing each other, in which she can see herself receding ad infinitum. She then says "Bloody Mary" three times (as in the folklore) before ducking, conjuring an infinite number of malevolent spirits who jump from the mirror towards each other. It's not clear if they simply collide, or pass into the opposing mirror.

Douglas Hofstadter is the author of Gödel, Escher, Bach and I Am a Strange Loop. In the latter book he focuses on the idea of minds being self-referential. "In the end, we are self-perceiving, self-inventing, locked-in mirages that are little miracles of self-reference". This blends with the idea of the images of the person looking in the mirror being reflected endlessly.


[Megan sets up a full mirror adjacent to a bathroom-counter mirror.]
[Megan looks through the bathroom counter mirror to see the infinite reflections.]
Megan: Bloody Mary, Bloody Mary, Bloody Mary.
[Megan ducks as the infinite Bloody Marys pop out between the two mirrors above her head.]

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Am i the only one who think of the ne555? 21:46, 11 December 2012 (UTC)

No idea. What I was thinking was who reads books like that?

(There again who responds to sites like this?) And: Shouldn't the mirrors be at a slight angle to one another?

I used Google News BEFORE it was clickbait (talk) 18:06, 30 January 2015 (UTC)

A slight angle would amplify with each reflection breaking the chain. It would make more sense for them to be parallel but off-center from one another. flewk (talk) 07:38, 5 January 2016 (UTC)


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