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Lateral thinking puzzles: Welcome the unexpected

Lateral thinking puzzles: Welcome the unexpected

Another puzzle in this series to test your lateral thinking skills! Paul Sloane shares a brainteaser designed to make you expect the unexpected

Let’s start with a lateral thinking puzzle. A man and his wife have dinner in an expensive restaurant. The food is first-class, the kitchen is spotless, the staff are excellent, everything is perfectly clean. They are not served anything to which they are allergic. But just after the meal the couple are violently sick. Why?

Welcome the unexpected

We often treat an unexpected or surprising happening as an irritation or distraction. It delays us from getting on with the job, so we quickly work around it. But sometimes it pays to step back and ponder the meaning of what serendipity has just handed us. Consider these unexpected occurrences.

Cup of tea

In New York in 1908, a tea merchant sent customers samples of tea leaves in small silken sachets for them to try. Customers were supposed to empty out the contents but instead some put the whole silk bag into the teapot and then added hot water.

In 1928, a Scottish bacteriologist returned from his vacation to find that one of his petri dishes had a strange mould growing in it.

In the early 1940s, a Swiss engineer went for a walk with his dog in the Jura mountains.  When he came home, he saw that his trousers and the dog’s fur contained many tiny seed burrs.

"Each of these incidents could have been treated as an annoying accident"

In 1946, an engineer at Raytheon discovered that a sweet in his pocket melted when he worked near an active radar tube.

In the 1970s, a technician working for a music accessory company wired a circuit incorrectly. The component made a weird moaning sound.

In 1989, a pharmaceutical company ran a clinical trial on an experimental drug which was designed to treat heart-related chest pains. It was not particularly effective in that regard but men on the trial reported an unusual side-effect.

Each of these incidents could have been treated as an annoying accident. Most people might have ignored the customers, cleaned the petri dishes, brushed out their trousers, removed the sticky sweet or rewired the circuit correctly. Fortunately for us, the protagonists in these stories all welcomed the unexpected event, investigated, and then acted.

History-making discoveries

When Thomas Sullivan heard that customers were happy with this new arrangement, he designed small containers for large scale production. He created the teabag. He made bags of gauze and then paper. He later added string and a tag so the bag could be easily removed. Incidentally, according to the Daily Mirror, a survey by English Heritage showed that people rated the teabag as one of the most important inventions of all time alongside the wheel and the internet.

Sir Alexander Fleming saw that the mould had rejected the bacteria in the dish. He had discovered penicillin—almost by accident. It was a piece of good fortune that led to the development of antibiotics and the saving of millions of lives.

George de Mestral examined the burrs under a microscope and saw that they had tiny hooks which caught in the trouser fabric. He went on to develop a new way to fasten materials—Velcro. The word comes from the French words velours and crochet: a Velvet Hook.


Percy Spencer developed the world’s first microwave oven because of this accident.

Scott Burnham adapted the strange wail into a guitar-pedal sound. He invented the Rat, a pedal that thousands of bands from Nirvana to Radiohead used to enhance their music.

Pfizer had stumbled onto Viagra.

In her book Inventology, Pagan Kennedy claims that almost half of all inventions started with a serendipitous process. Often this was the result of ideas or discoveries that people had while working on something else.

"When something unexpected happens don’t get annoyed, get curious"

Kennedy goes on to say that inventors are often polymath connectors, “who by luck or design are able to bring together knowledge from several fields.” She points out that the people most likely to solve problems on the Innocentive crowdsourcing site are outsiders to the field of the problem.

When something unexpected happens don’t get annoyed, get curious. Find out why. The customer with a weird complaint or a weird use for your product is 100 times more interesting than the customer who is happy using your product in a conventional way. Welcome the surprising. Lateral thinkers are open-minded and quick to learn from accidents. They are ready to observe and adapt when the unexpected happens.

Answer to the puzzle

The restaurant was on board a cruise liner which ran into an unexpected storm.

Paul Sloane is a leading speaker and best-selling author of lateral thinking and innovation books, with his new book Lateral Thinking for Every Day available to purchase now (Kogan Page, £12.99)

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