Makes Sense

THREE = 03

Advance each character in that expression four steps in the alphabet or the number line and you get:

XLVII = 47

(Discovered by Dave Morice and Daniel McGrath. From “Kickshaws,” Word Ways 32:4 [November 1999], 283-293.)

Podcast Episode 249: The Robbers Cave Experiment

robbers cave

In 1954 a social psychologist started a war between two teams of fifth graders at an Oklahoma summer camp. He wanted to investigate the sources of human conflict and how people might overcome them. In this week’s episode of the Futility Closet podcast we’ll review the Robbers Cave Experiment and examine its evolving reputation.

We’ll also dredge up a Dalek and puzzle over a hazardous job.


Butler University mathematician Jerry Farrell can control coin flips.

Nashville attorney Edwin H. Tenney gave a baffling Independence Day speech in 1858.

Sources for our feature on the Robbers Cave experiment:

Muzafer Sherif et al., Intergroup Conflict and Cooperation: The Robbers Cave Experiment, 1961.

Gina Perry, The Lost Boys: Inside Muzafer Sherif’s Robbers Cave Experiment, 2018.

Ayfer Dost-Gozkan and Doga Sonmez Keith, Norms, Groups, Conflict, and Social Change: Rediscovering Muzafer Sherif’s Psychology, 2015.

Paul Bloom, Just Babies: The Origins of Good and Evil, 2013.

Gina Perry, “The View From the Boys,” Psychologist 27:11 (November 2014), 834-836.

Ralph H. Turner, “Some Contributions of Muzafer Sherif to Sociology,” Social Psychology Quarterly 53:4 (December 1990), 283-291.

Muzafer Sherif, “Superordinate Goals in the Reduction of Intergroup Conflict,” American Journal of Sociology 63:4 (January 1958), 349-356.

Gregory M. Walton and Carol S. Dweck, “Solving Social Problems Like a Psychologist,” Perspectives on Psychological Science 4:1 (January 2009), 101-102.

O.J. Harvey, “Muzafer Sherif (1906–1988),” American Psychologist 44:10, October 1989, 1325-1326.

Elton B. McNeil, “Discussions and Reviews: Waging Experimental War: A Review,” Journal of Conflict Resolution 6:1 (March 1962), 77.

Alex Haslam, “War and Peace and Summer Camp,” Nature 556:7701 (April 19, 2018), 306-307.

Steven N. Durlauf, “A Framework for the Study of Individual Behavior and Social Interactions,” Sociological Methodology 31 (2001), 47.

Gary Alan Fine, “Review: Forgotten Classic: The Robbers Cave Experiment,” Sociological Forum 19:4 (December 2004), 663-666.

Andrew Tyerman and Christopher Spencer, “A Critical Test of the Sherifs’ Robber’s Cave Experiments: Intergroup Competition and Cooperation Between Groups of Well-Acquainted Individuals,” Small Group Research 14:4 (November 1983), 515-531.

Samuel L. Gaertner et al., “Reducing Intergroup Conflict: From Superordinate Goals to Decategorization, Recategorization, and Mutual Differentiation,” Group Dynamics: Theory, Research, and Practice 4:1 (March 2000), 98-114.

Furkan Amil Gur, Benjamin D. McLarty, and Jeff Muldoon, “The Sherifs’ Contributions to Management Research,” Journal of Management History 23:2 (2017), 191-216.

Anna E. Kosloski, Bridget K. Welch, “Confronting Student Prejudice With ‘Mario Kart’ Nintendo Wii,” Social Thought and Research 31 (2010), 79-87.

Carol Tavris, “Thinking Critically About Psychology’s Classic Studies,” Skeptic 19:4 (2014), 38-43, 64.

Michael J. Lovaglia, “From Summer Camps to Glass Ceilings: The Power of Experiments,” Contexts 2:4 (Fall 2003), 42-49.

J. McKenzie Alexander, “Group Dynamics in the State of Nature,” Erkenntnis 55:2 (September 2001), 169-182.

Maria Konnikova, “Revisiting Robbers Cave: The Easy Spontaneity of Intergroup Conflict,” Scientific American, Sept. 5, 2012.

Peter Gray, “A New Look at the Classic Robbers Cave Experiment,” Psychology Today, Dec. 9, 2009.

David P. Barash, “Why People Kill,” Chronicle of Higher Education, Nov. 8, 2015.

Barbara McMahon, “I Survived the Real-Life Lord of the Flies,” Times, April 25, 2018, 2.

Leyla Sanai, “‘The Lost Boys: Inside Muzafer Sherif’s Robbers Cave Experiment’, by Gina Perry – Review,” Spectator, April 28, 2018.

Anoosh Chakelian, “The Lasting Wounds of Robbers Cave,” New Statesman 147:5425 (June 29-July 5, 2018), 16-17.

Judy Golding Carver, “What Lord of the Flies Is Really About,” Guardian, April 20, 2018, 8.

Eleanor Learmonth and Jenny Tabakoff, “‘What Are We? Humans? Or Animals? Or Savages?'” Independent on Sunday, March 16, 2014, 26.

Darragh McManus, “The Real-Life ‘Lord of the Flies,'” Irish Independent, May 5, 2018, 18.

David Shariatmadari, “A Real-Life Lord of the Flies: The Troubling Legacy of the Robbers Cave Experiment,” Guardian, April 16, 2018.

Gina Perry, “Real-Life Lord of the Flies,” Qatar Tribune, Feb. 24, 2018.

Peter Waterson, “Letters: Love-Hate,” Guardian, Oct. 18, 2001, 25.

Listener mail:

Wikipedia, “Mojibake” (accessed May 10, 2019).

Victoria Ward, “‘Weekend Foggy Earphones’: How Three Random Words Helped Police Come to Rescue of Mother and Daughter,” Telegraph, March 25, 2019.

Tiffany Lo, “How Mum and Daughter Were Saved by Saying Words ‘Weekend Foggy Earphones’ to Cops,” Mirror, March 26, 2019.

Jane Wakefield, “Three-Unique-Words ‘Map’ Used to Rescue Mother and Child,” BBC News, March 26, 2019.

Mark Bridge, “Valerie Hawkett: Three Words Find Woman Who Crashed Car in a Field,” Times, March 26, 2019.

“Dr Who Dalek Found in Pond,” Telegraph, March 4, 2009.

Wikipedia, “Dalek” (accessed May 10, 2019).

This week’s lateral thinking puzzle was contributed by listener Sam Dyck, who, for background, sent this summary of 2017 fatal occupation injuries from the U.S. Bureau of Labor Statistics.

You can listen using the player above, download this episode directly, or subscribe on Google Podcasts, on Apple Podcasts, or via the RSS feed at

Please consider becoming a patron of Futility Closet — you can choose the amount you want to pledge, and we’ve set up some rewards to help thank you for your support. You can also make a one-time donation on the Support Us page of the Futility Closet website.

Many thanks to Doug Ross for the music in this episode.

If you have any questions or comments you can reach us at Thanks for listening!


In January 1942, a series of letters to the Daily Telegraph complained that the newspaper’s crossword was too easy — anyone might solve it in a matter of minutes, they said. Accordingly the chairman of a London club offered to donate £100 to charity if anyone could solve a given crossword in 12 minutes. Editor Arthur Watson arranged a competition in the paper’s Fleet Street newsroom, and five people won the competition (though the fastest was later disqualified for misspelling a word). Several were later hired to work at Bletchley Park breaking German military codes.

The Telegraph published the “time test” puzzle later that month, and presented it again in 2014, inviting readers to try to solve it in 12 minutes. “Could you have been a codebreaker at Bletchley Park?”


Last August, researchers at Rome University produced tiny portraits of Albert Einstein and Charles Darwin by modifying E. coli cells to respond to light patterns. Bacteria that received more light would swim faster, so over time they tended to concentrate in the darker parts of a negative image.

Lead author Giacomo Frangipane said in a statement, “Much like pedestrians who slow down their walking speed when they encounter a crowd, or cars that are stuck in traffic, swimming bacteria will spend more time in slower regions than in faster ones.”

Using the same technique, they created a (tiny) version of the Mona Lisa.

Drawing Customers

Seoul’s Drawing Cafe is styled like a two-dimensional cartoon. Inspired by the Korean television show W, in which characters move between the real world and a fantasy world inside a webtoon, the café has designed its furniture, walls, floors, mugs, dishes, and cutlery to look like flat line drawings.

More on the café’s Instagram page.

Image: Wikimedia Commons

The ninth British expedition to Everest brought along a journalist, James Morris of the London Times. To avoid losing a scoop to other journalists who might intercept their wire messages, Morris and the editors worked out a series of code phrases with secret meanings:

Snow conditions bad: Everest climbed
Wind still troublesome: Attempt abandoned
South Col untenable: Band
Lhotse Face impossible: Bourdillon
Ridge camp untenable: Evans
Withdrawal to West Basin: Gregory
Advanced base abandoned: Hillary
Camp 5 abandoned: Hunt
Camp 6 abandoned: Lowe
Camp 7 abandoned: Noyce
Awaiting improvement: Tenzing
Further news follows: Ward

On May 30, 1953, Morris gave a seemingly innocuous message to a Sherpa runner: Snow conditions bad stop advanced base abandoned yesterday stop awaiting improvement. On June 2, on an inside page under the headline “Everest Conquered,” the Times reported that Edmund Hillary and Tenzing Norgay had reached the summit on May 29. With that the Times won historic credit for breaking the story; it fell to the Daily Express to follow up with front-page coverage.

(From Paul Lunde, ed., The Book of Codes, 2009.)

A Fashion Puzzle

According to a British censorship manual from World War II (PDF, page 14), this sketch, published in a wartime newspaper, contained a secret message, ostensibly hidden in Morse code in the arrangement of dots and lines on the women’s dresses. The message is “Heavy reinforcements for the enemy expected hourly,” or, in the German original, “Massive Feindverstärkungen werden stündlich erwartet.”

A second message is hidden in the signature, written in a French shorthand. In English this read “Before Arras”; in German it was probably “Vor Arras.”

Unfortunately, the manual doesn’t explain the method by which these messages were hidden, and to date no one has been able to re-establish it. Where are these messages to be found in the image? Encryption expert Klaus Schmeh writes, “So far, I could neither find the morse message nor the shorthand message. I even went to the British Archive in London to look at the original document and to take high resolution photographs. It didn’t help.”

On his blog, Schmeh presents one of these high-resolution images, as well as a second mystery from the same manual. See the comments on that post for some suggestions from his readers.


Brad Taylor offered this baseball puzzle in the October 2001 issue of MIT Technology Review:

The Red Sox beat the Orioles 9 to 4 in 17 innings. Where was the game played?

Click for Answer


Prove that if n is a positive integer greater than 1, then

\displaystyle 1 + \frac{1}{2} + \frac{1}{3} + \dots + \frac{1}{n}

is not an integer.

Click for Answer