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How to Use Toilet Paper

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Certain aspects of human life are simultaneously private and universal -- everyone experiences the same stuff privately and almost no one talks about it. Pretty much everything that happens in the bathroom falls into this category, which is why I was amazed to discover that serious thought has gone into the challenges presented by toilet paper. Here are a few examples.

The Toilet Paper Algorithm

Design guru Don Norman decided to confront a common toilet paper crisis: the problem of the roll running out just when you need it most. When remodeling his home, Norman installed a dual-roll toilet paper dispenser, under the theory that there'd always be a second roll available for just such emergencies. But he quickly found that, for some reason, both rolls seemed to run out at the same time!

Norman applied some logical thinking to his problem, resulting in the article Toilet Paper Algorithms: I didn't know you had to be a computer scientist to use toilet paper. The gist of it is that Norman and his wife were subconsciously selecting whatever roll was larger at any given time, leading them both to become roughly the same size, thus running out at the same time. (Read the article for more details on the various available toilet paper's neat.)

For the record, Norman determined that the optimal strategy for using toilet paper in a dual-roll holder is to always use the smaller roll. This will tend to drive one roll to become empty, but will leave a full roll available.

Norman isn't alone in his analysis of toilet paper roll consumption -- Donald E. Knuth published a mathematics paper entitled The Toilet Paper Problem in The American Mathematical Monthly in 1984, including equations for analysis of toilet paper usage.

The Fold Versus Crumple Debate

I'll try to put this as delicately as I can. Apparently there's a significant debate about whether it's better to fold several sheets of paper, or crumple them together in a bunch. One major argument in favor of the "fold" method is that depending on the quality of your paper and your folding technique, you can refold (and thus reuse) a single set of sheets. The counter-argument is that this is super-gross. I have my own opinions on this issue, but let's just say I've tried multiple methodologies over the years and feel that I've perfected my technique.

So what's the distribution of crumplers versus folders in the wild? An online toilet paper usage survey has received almost 5,000 responses. At the moment, the folders are slightly in the lead (52%), but tend to be a little older than crumplers. Also, far more crumplers are male than female (70% of crumplers in the survey are male). You can take the survey or just hit the 'View' button to see the results without contributing your own.

Toilet Paper Requisition Denied

Here's some fun WWII trivia. Lieutenant Commander J. W. Coe of the submarine USS Skipjack requested 150 rolls of toilet paper from the supply officer at Mare Island Naval Base in July of 1941. The request was denied in November of 1941 with a notation saying, "Cancelled -- cannot identify." By June 1942 the situation onboard USS Skipjack was dire, and Coe sent another request, reading in part:

During the 11-3/4 months elapsing from the time of ordering the toilet paper and the present date, USS SKIPJACK personnel, despite their best efforts to await delivery of the subject material, have been unable to wait on numerous occasions, and the situation is now quite acute, particularly during depth-charge attacks by the "back stabbers."


SKIPJACK personnel during this period have become accustomed to the use of "crests," i.e., the vast amount of incoming non-essential paper work, and in so doing feel that the wish of the Bureau of Ships for reduction of paper work is being complied with, thus killing two birds with one stone.

Read the rest at the wonderful Snopes page detailing the event.

Got any toilet paper trivia, or an opinion on fold-versus-crumple? Share it with us in the comments!

(Toilet paper photo courtesy of Brandon Blinkenberg and Wikimedia Commons.)

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Courtesy University of Manchester
148 Lost Alan Turing Papers Discovered in Filing Cabinet
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Courtesy University of Manchester

You never know what you’re going to uncover when you finally get around to combing through that decades-old filing cabinet in the back room. Case in point: The University of Manchester recently unearthed 148 long-lost papers belonging to computer science legend Alan Turing, as ScienceAlert reports.

The forgotten papers mostly cover correspondence between Turing and others between 1949 and his death in 1954. The mathematician worked at the university from 1948 on. The documents include offers to lecture—to one in the U.S., he replied, “I would not like the journey, and I detest America”—a draft of a radio program he was working on about artificial intelligence, a letter from Chess magazine, and handwritten notes. Turing’s vital work during World War II was still classified at the time, and only one document in the file refers to his codebreaking efforts for the British government—a letter from the UK’s security agency GCHQ. The papers had been hidden away for at least three decades.

A typed letter to Alan Turing has a watermark that says 'Chess.'
Courtesy University of Manchester

Computer scientist Jim Miles found the file in May, but it has only now been sorted and catalogued by a university archivist. "I was astonished such a thing had remained hidden out of sight for so long," Miles said in a press statement. "No one who now works in the school or at the university knew they even existed." He says it’s still a mystery why they were filed away in the first place.

The rare discovery represents a literal treasure trove. In 2015, a 56-page handwritten manuscript from Turing’s time as a World War II codebreaker sold for more than $1 million.

[h/t ScienceAlert]

Can You Figure Out How Many Triangles Are in This Picture?

Time for another brain teaser. How many triangles do you see here? A Quora user posted the image above (which we spotted on MSN) for fellow brainiacs to chew on. See if you can figure it out. We’ll wait.


So, as you can see, all the smaller triangles can combine to become bigger triangles, which is where the trick lies. If you count up every different triangle formed by the lines, you should get 24. (Don’t forget the big triangle!)

Some pedantic Quora users thought it through and realized there are even more triangles, if you really want to go there. There’s a triangle formed by the “A” in the signature in the right-hand corner, and if we’re counting the concept of triangles, the word “triangle” counts, too.

As math expert Martin Silvertant writes on Quora, “A triangle is a mathematical idea rather than something real; physical triangles are by definition not geometrically perfect, but approximations of triangles. In other words, both the pictorial triangles and the words referring to triangles are referents to the concept of a triangle.” So yes, you could technically count the word “triangle.”  (Silvertant also includes a useful graphic explaining how to find all the pictorial triangles.)

Check out the whole Quora discussion for in-depth explainers from users about their methods of figuring it out.

[h/t MSN]


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