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The Most Sobering Mistake in U.S. History

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Prohibition: It certainly seemed like a great idea at the time: Just outlaw liquor and, bam!, goodbye social ills of every stripe—from the Germans to the Irish. Yes, pandering to xenophobia was the favorite tactic among Prohibition crusaders, who painted saloons as a filthy underworld brimming with undesirable foreigners. Ultimately, however, the event that probably did the most to push America toward Prohibition was the country's 1917 entry into World War I. Prohibitionists began arguing that all of America's resources were needed to fight the German menace, using the logic that, if the government needed to maximize agricultural production to win the war, then it couldn't waste all that grain on booze. Apparently, their message worked. By the end of 1917, the majority of Americans were living in alcohol-free states or counties.

The Dry Party began on January 17, 1920, when the Volstead Act went into effect. All across the nation, Prohibitionists got down and boogied—as best they could. In Norfolk, Va., this included a mock funeral for the alcohol effigy "John Barleycorn," featuring 20 pallbearers and a horse-drawn hearse.

The Wet Party began on January 17, 1920. Within hours of the Volstead Act's passing, bandits reportedly began looting train yards and warehouses, making off with thousands of dollars worth of whiskey that had been reserved for medicinal uses. Despite steep penalties (a first offense meant a potential $2,000 fine and 18 months in prison) Americans went right on producing, selling, and drinking booze.

In fact, statistics indicate that more Americans were drinking than ever before.

Far from being dead, saloons were flourishing. By 1930, there were 32,000 speakeasies in New York City—more than twice the number of legal drinking establishments in town before Prohibition. Two years later, Franklin D. Roosevelt ran for the presidency on a platform of "a New Deal and a pot of beer for everyone." For a nation beleaguered by alcohol-financed organized crime, the offer was too good to pass up. Six months after Roosevelt entered office, the Not-So-Great Experiment came to an end.


20-mistaikes.jpg---This summer, mental_floss is re-running parts of "The 20 Greatest Mistaikes in History," Maggie Koerth-Baker's cover story from March-April 2007. To order the back issue, click here. To see other installments in this series, click here.

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iStock // Ekaterina Minaeva
Man Buys Two Metric Tons of LEGO Bricks; Sorts Them Via Machine Learning
May 21, 2017
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iStock // Ekaterina Minaeva

Jacques Mattheij made a small, but awesome, mistake. He went on eBay one evening and bid on a bunch of bulk LEGO brick auctions, then went to sleep. Upon waking, he discovered that he was the high bidder on many, and was now the proud owner of two tons of LEGO bricks. (This is about 4400 pounds.) He wrote, "[L]esson 1: if you win almost all bids you are bidding too high."

Mattheij had noticed that bulk, unsorted bricks sell for something like €10/kilogram, whereas sets are roughly €40/kg and rare parts go for up to €100/kg. Much of the value of the bricks is in their sorting. If he could reduce the entropy of these bins of unsorted bricks, he could make a tidy profit. While many people do this work by hand, the problem is enormous—just the kind of challenge for a computer. Mattheij writes:

There are 38000+ shapes and there are 100+ possible shades of color (you can roughly tell how old someone is by asking them what lego colors they remember from their youth).

In the following months, Mattheij built a proof-of-concept sorting system using, of course, LEGO. He broke the problem down into a series of sub-problems (including "feeding LEGO reliably from a hopper is surprisingly hard," one of those facts of nature that will stymie even the best system design). After tinkering with the prototype at length, he expanded the system to a surprisingly complex system of conveyer belts (powered by a home treadmill), various pieces of cabinetry, and "copious quantities of crazy glue."

Here's a video showing the current system running at low speed:

The key part of the system was running the bricks past a camera paired with a computer running a neural net-based image classifier. That allows the computer (when sufficiently trained on brick images) to recognize bricks and thus categorize them by color, shape, or other parameters. Remember that as bricks pass by, they can be in any orientation, can be dirty, can even be stuck to other pieces. So having a flexible software system is key to recognizing—in a fraction of a second—what a given brick is, in order to sort it out. When a match is found, a jet of compressed air pops the piece off the conveyer belt and into a waiting bin.

After much experimentation, Mattheij rewrote the software (several times in fact) to accomplish a variety of basic tasks. At its core, the system takes images from a webcam and feeds them to a neural network to do the classification. Of course, the neural net needs to be "trained" by showing it lots of images, and telling it what those images represent. Mattheij's breakthrough was allowing the machine to effectively train itself, with guidance: Running pieces through allows the system to take its own photos, make a guess, and build on that guess. As long as Mattheij corrects the incorrect guesses, he ends up with a decent (and self-reinforcing) corpus of training data. As the machine continues running, it can rack up more training, allowing it to recognize a broad variety of pieces on the fly.

Here's another video, focusing on how the pieces move on conveyer belts (running at slow speed so puny humans can follow). You can also see the air jets in action:

In an email interview, Mattheij told Mental Floss that the system currently sorts LEGO bricks into more than 50 categories. It can also be run in a color-sorting mode to bin the parts across 12 color groups. (Thus at present you'd likely do a two-pass sort on the bricks: once for shape, then a separate pass for color.) He continues to refine the system, with a focus on making its recognition abilities faster. At some point down the line, he plans to make the software portion open source. You're on your own as far as building conveyer belts, bins, and so forth.

Check out Mattheij's writeup in two parts for more information. It starts with an overview of the story, followed up with a deep dive on the software. He's also tweeting about the project (among other things). And if you look around a bit, you'll find bulk LEGO brick auctions online—it's definitely a thing!

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Name the Author Based on the Character
May 23, 2017
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