Misdirection is an old magician's tactic, a trick to get the audience to look in the wrong place at the right time. "Say hello to my lovely assistant in the impossibly short dress over to the left, while I stuff this rabbit into a top hat over here on the right."
The goal of misdirection is psychological - to set the audience's mind on the wrong trail. This is what Stewart Coffin likes to do with his geometric puzzles. He knows what his audience is thinking; he knows how they expect to solve puzzles. So he twists that and lets them misdirect themselves.
Coffin, a 77-year-old from Andover who is a superstar in the world of puzzle designers, lays "The Cruiser" out on a table in his kitchen. The puzzle is a simple two-dimensional "fit-together" puzzle, along the lines of a jigsaw puzzle, and it gets its name because Coffin likes to take it on cruise ships to confound his fellow passengers.
The Cruiser features four pieces and a rectangular wooden frame. "Your job," he says with a knowing smile, "is to fit them into the frame."
Each piece is wedge-shaped, with one right angle; and it is those right angles that he's going to use to toy with you. "You would normally think that you'd put the right angles into the corners of the tray," said Jerry Slocum, a prominent puzzle historian and collector who considers Coffin to be perhaps the best puzzle designer of all time. "You'll never be able to solve a Stewart Coffin puzzle thinking like this."
The misdirection of The Cruise doesn't end there. Not only do you not put the right angles into the corners of the frame; you don't put anything in the corners. In the solved puzzle, there's an empty space in each corner. He never said the pieces had to fill the frame, just that they had to fit.
"His puzzles have the same kind of elegance and appeal as a theorem does," said Peter Winkler, a professor of mathematics and computer science at Dartmouth. "To be able to do what he does, he has to have a very powerful understanding of geometric objects.
"I can't even begin to describe how he does it," said Winkler, who invited Coffin to speak at a symposium on the design of mechanical puzzles on Saturday as part of American Association for the Advancement of Science's annual meeting. "I can only admire it."
Coffin began his career as an engineer, and spent some time in the '50s working at MIT in the very early days of the digital computing lab. But he eventually left the professional world and turned a passion for whitewater canoeing into a business designing and building fiberglass canoes and paddles. After a few years, "the fumes took their toll," he said, and he began tinkering with puzzles, which had been a passion since childhood.
In the 1970s, Coffin made his name among "puzzle people" when he invented the three-dimensional polyhedral puzzle, which involves interlocking pieces that combine to form a multi-planed solid. When
Most of Coffin's puzzles have been produced in limited numbers, usually handmade by Coffin out of fine wood. He has sold most of them at craft shows as elegant art objects, or to wives who "wanted something to drive their husbands crazy." Today, a Coffin original can fetch thousands of dollars from collectors.
Coffin said the key to a good puzzle is simplicity; and that's also what makes it so challenging to come up with something that hasn't been done before. Designing a puzzle, he says, involves a lot of trial and error; he compares it to looking for buried treasure. "You dig and you dig and most of the time you find nothing. But sometimes, you uncover a gem."
Coffin said he enjoys watching people try to solve his puzzles, though there's a certain bit of frustration in watching them mess up. But in the end, for the puzzle solver and the puzzle designer, there's always the payoff.
"There's a great satisfaction when things go together nicely," he said, "especially in this world where so much does not."
Hometown: Born in North Amherst; lives in Andover.
Education: Graduated from UMass-Amherst in 1952 with a degree in electrical engineering.
Family: Partner, Mary Dow, an educator; daughters: Abbie White, 47, a chemist in Hardwick; Tammis Coffin, 46, of Stockbridge, who works for the Massachusetts Trustees of Reservations; Margie Brown, 44, lives in Lincoln and works for the National Park Service.
Three classic puzzles he admires: The Soma cube; Dad's Puzzle; and the Buttonhole Puzzle.
Hobbies: Enjoys whitewater canoeing; plays the fiddle and the banjo.
UPDATE
A recent Meeting the Minds featured Kevin Short, a mathematics professor at the University of New Hampshire who used complex mathematical algorithms to help restore a wire recording of a 1949 performance by folk legend Woody Guthrie. Last week, Short won a Grammy award for that work, taking home a gold-plated gramophone in the Best Historical Album category for his work. Score one for the math nerds.
