Martin Gardner was a giant in the recreational math world — many of the puzzles we take on each week here at Numberplay are direct descendants of the many counter-intuitive conundra that Gardner curated in the 20th century. He was such a significant force in math puzzles that we forget — or have a hard time really believing — that he had other lives, including that of a popular and influential magician. This week I’m pleased to present a book that captures this magical life: Martin Gardner’s Impromptu. The book is absolutely gorgeous: beautifully designed and full of detail, with hundreds of pages of original notes and sketches by Martin Gardner (the book itself is over 800 pages long). Click here to enjoy selections from the color section of the book, and here for an introduction to MiniTrix, a series of short videos featuring Martin Gardner performing various impromptu tricks.  I asked Todd Karr, Chief Enchantment Officer for The Miracle Factory, which published the book, to say a bit about producing Impromtu, and to also share a magic trick, or “effect,” as it’s known in the magic business, for us to ponder this week. Here’s Mr. Karr:  Sorting through the late Martin Gardner’s secret magic files felt like wandering through a Lewis Carroll forest of towering stacks of aging index cards and clippings, an immense world springing from one man’s seemingly limitless imagination and curiosity. Best known as a prolific writer and beloved Scientific American columnist who regularly turned dry knowledge into fun and amazement, Gardner (1914-2010) was also in fact an accomplished magician. But like a scientist, he studied his craft in fine detail, jotting down nearly every nuance of the magician’s art that he gleaned from the many top wizards who welcomed him into their inner circles.  Although he could in fact pull off technically impressive magic, Gardner especially loved the somewhat minimalist secrets of a wide-ranging genre that magicians deem “impromptu magic,” a casual branch of trickery that’s usually performed for friends and family after dinner with everyday objects. Classics include vanishing your dinner knife, passing a salt shaker through the tabletop, and bouncing a dinner roll. They’re quick feats to perform for friends at a diner over coffee and dessert, almost always with more of a sense of fun than deep mystery.  Precisely arranged and covered with meticulous fountain-pen thoughts on magic effects and bar bets, these decades of ideas are now included in Impromptu, an expanded edition of Martin’s already-mammoth Encyclopedia of Impromptu Magic.  Gardner’s epic book collected his 1950s columns on impromptu magic that he’d written for the long-defunct Hugard’s Magic Monthly featuring 1200 items from his magic files, serialized in neat categories from Apples to Zippers. It took the journal almost eight years to publish it all.  Martin and I had agreed to create the current expanded edition several years ago. Part of the excitement for me was the chance to see some of his genius first-hand. Into his 90s, Gardner still kept up with all the latest hot-shot magic trends – such as a fad for rubber band tricks in the 1980s – and sent me page after page of typewritten additional items marked in pen with his charming drawings. That was on top of the bulging manila folders of his vintage notes, which dated back to the 1930s when a teenaged Gardner first began documenting now-forgotten magic methods, devious bar bets, and matchstick puzzles, often inventing new ones along the way. The dazzling contents of his treasures are straight out of From The Mixed-Up Files of Mrs. Basil E. Frankweiler: brittle brown news clippings about bygone magicians, hastily typed notes about sugar-lump stunts, comical photos of funny faces from Life, a flattened Camel pack for bar gags, and three different paper devices for checking what city printed your dollar bill, often tucked in alongside friendly notes from some of the world’s top scholars exchanging schoolboy pranks with Gardner.  Now, a logical person might wonder why a magician would reveal his secrets in print in the first place. The truth is Gardner-level paradoxical: Because the best place to hide secrets is out in the open, in a book. Only someone with a genuine interest will seek it out, and his motivated search will qualify him to possess the secrets. Plus, after all that work finding the lowdown, most readers likely won’t turn around and spill the beans to just anyone.  So since you’ve read this far, you’re rewarded with a phenomenal Martin Gardner effect that you can try right now. The original appears in his 1966 anthology Martin Gardner’s New Mathematical Diversions from Scientific American. I’ve adapted it so one person can enjoy it without an audience or preparation.  Martin Gardner Reads Your Mind  First, on the back of a place-mat or anything handy, draw a big square, divide it into nine spaces, and fill in the words as shown in the figure below (or here):  Now, just follow these instructions, or read them aloud to a friend to let Martin blow his mind:  How does it work? To understand Martin’s secret powers, you’ll either have to do some deep Gardner-like thinking or seek out his 1966 book!  Thank you, Mr. Karr. With that we wrap up the week. As always, once you’re able to read comments for this post, use Gary Hewitt’s Enhancer to correctly view formulas and graphics  Note: book cover image copyright Jim Steranko 2015 and used with permission. Excerpts from Impromptu copyright 2015 The Miracle Factory and the Martin Gardner Literary Interests.  The following show Martin Gardner performing for the MiniTrix series. (Ah, the 1950’s!)  Here’s David Copperfield presenting his own mind-reading magic.  To help maintain the mystery of this week’s magic trick, we won’t be providing an official solution.
Do you believe in mind reading? Try this experiment in clairvoyance with the late recreational mathematician, Martin Gardner.