Poem Codes

During World War II the British Special Operations Executive used poetry to communicate with its agents in enemy territory. The sender and receiver would agree in advance on a poem, and by numbering its letters they produced a simple cipher that could be used to transmit messages. Because both sides could memorize the poem, there was no codebook to lose, but the Nazis could break the code fairly easily, particularly if the poem was well known.

Realizing this, SOE codes officer Leo Marks began to introduce original poems of his own creation. He gave this one to French agent Violette Szabo in March 1944:

The life that I have is all that I have,
And the life that I have is yours.
The love that I have of the life that I have
Is yours and yours and yours.

A sleep I shall have, a rest I shall have,
Yet death will be but a pause.
For the peace of my years in the long green grass
Will be yours and yours and yours.

Marks had written it three months earlier in memory of his girlfriend Ruth, who had died in a plane crash in Canada. The poem became famous when it was read in the 1958 film Carve Her Name With Pride, about Szabo’s exploits in the war. Unfortunately, Szabo herself was captured, tortured, and killed before she could transmit any messages.

Moving Constants

circle theorems

If you mark two points on a circle, A and B, and a third point T, then angle ATB remains constant as T moves along the segment between A and B. (If you mark a point S in the circle’s other segment then you get another constant angle, ASB, and ASB = 180 – ATB.)

If two circles intersect at A and B and we move T as before along the segment opposite the second circle, and we extend TA and TB to P and Q on the second circle, then the length of chord PQ remains constant as T moves.

(From David Wells, The Penguin Dictionary of Curious and Interesting Geometry, 1992.)

Last Orders

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About noon, when Major Pendleton came into the room, he asked, ‘Who is preaching at headquarters today?’ He was told that Mr. Lacy was, and that the whole army was praying for him. ‘Thank God,’ he said; ‘they are very kind to me.’ Already his strength was fast ebbing, and although his face brightened when his baby was brought to him, his mind had begun to wander. Now he was on the battle-field, giving orders to his men; now at home in Lexington; now at prayers in the camp. Occasionally his senses came back to him, and about half-past one he was told that he had but two hours to live. Again he answered, feebly but firmly, ‘Very good; it is all right.’ These were almost his last coherent words. For some time he lay unconscious, and then suddenly he cried out: ‘Order A.P. Hill to prepare for action! Pass the infantry to the front! Tell Major Hawks –‘ then stopped, leaving the sentence unfinished. Once more he was silent; but a little while after he said very quietly and clearly, ‘Let us cross over the river, and rest under the shade of the trees,’ and the soul of the great captain passed into the peace of God.

— George Francis Robert Henderson, Stonewall Jackson and the American Civil War, 1903

Condolence

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A letter from Abraham Lincoln to Fanny McCullough of Bloomington, Ill., whose father had died leading a charge in Mississippi, Dec. 23, 1862:

Dear Fanny: It is with deep regret that I learn of the death of your brave and kind father, and especially that it is affecting your young heart beyond what is common in such cases. In this sad world of ours sorrow comes to all, and to the young it comes with bitterer agony because it takes them unawares. The older have learned ever to expect it. I am anxious to afford some alleviation of your present distress. Perfect relief is not possible, except with time. You cannot now realize that you will ever feel better. Is not this so? And yet it is a mistake. You are sure to be happy again. To know this, which is certainly true, will make you some less miserable now. I have had experience enough to know what I say, and you need only to believe it to feel better at once. The memory of your dear father, instead of an agony, will yet be a sad, sweet feeling in your heart of a purer and holier sort than you have known before.

Please present my kind regards to your afflicted mother.

Your sincere friend,

A. Lincoln

The Barbershop Paradox

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In 1894 Lewis Carroll published a conundrum that, he wrote, presents “a very real difficulty in the Theory of Hypotheticals.” Suppose that Allen, Brown, and Carr run a shop. At least one of them must always be present to mind the shop, and whenever Allen leaves he always takes Brown with him. Now, suppose that Carr is out. In that case then if Allen is out then Brown must be in, in order to tend the shop. But we know that this isn’t true — we’ve been told that whenever Allen is out then Brown is out.

Since the supposition that Carr is out leads to a falsehood, then it must itself be false. Confusingly, the laws of logic seem to require that Carr never leave the shop.

“I greatly hope that some of the readers of Mind who take an interest in logic will assist in clearing up these curious difficulties,” Carroll wrote. Modern logicians would say that this is a simple error in reasoning, rather than a logical disaster. But what is the error?

Click for Answer

The Falling Chain

Here are two identical rope ladders with slanting rungs. One falls to the floor, the other onto a table. The ladders are released at the same time and fall freely, but the one on the left falls faster, as if the table is “sucking” it downward. Why does this happen?

Click for Answer

Dream Cuisine

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Image: Wikimedia Commons

In 1973 and 1974, the U.S. armed forces gave a food preference survey to about 4,000 members of the Army, Air Force, Navy, and Marine Corps.

The examiners included three fake dishes “to provide an estimate of how much someone will respond to a word which sounds like a food name or will answer without reading.”

The three fake dishes were “funistrada,” “buttered ermal,” and “braised trake.” The Washington Post reported, “Out of the 378 foods listed, braised trake came in 362, buttered ermal was 356 and funistrada finished several foods above the bottom 40, coming in between brussels sprouts and fried okra.”

For the record, here are the nine lowest-ranked foods, from the bottom up — all nine are so bad that service members ranked them beneath foods that don’t exist at all:

Buttermilk, skimmed milk, fried parsnips, low-calorie soda, mashed rutabagas, french fried carrots, prune juice, stewed prunes, french fried cauliflower.

(“The Ranking of the Favorites,” Washington Post, July 1, 1987. The Army survey is here: PDF.)

Podcast Episode 100: Lateral Thinking Puzzles

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Here are five new lateral thinking puzzles to test your wits and stump your friends — play along with us as we try to untangle some perplexing situations using yes-or-no questions.

Please consider becoming a patron of Futility Closet — on our Patreon page you can pledge any amount per episode, and all contributions are greatly appreciated. You can change or cancel your pledge at any time, and we’ve set up some rewards to help thank you for your support.

You can also make a one-time donation via the Donate button in the sidebar of the Futility Closet website.

Here are the sources for this week’s puzzles. In a couple of places we’ve included links to further information — these contain spoilers, so don’t click until you’ve listened to the episode:

Hotel: Listener Paul Sophocleous

Train: Listener Sean Gilbertson

Safe (more information): Listener David White

Robber (more information): Sharon Ross

Murder: Paul Sloane and Des MacHale, Intriguing Lateral Thinking Puzzles, 1996

You can listen using the player above, download this episode directly, or subscribe on iTunes or via the RSS feed at http://feedpress.me/futilitycloset.

If you have any questions or comments you can reach us at podcast@futilitycloset.com. Thanks for listening!