Before he turned physics upside down, a young Albert Einstein supposedly showed off his genius by devising a complex riddle involving this list of clues.
Can you resist tackling a brain teaser written by one of the smartest people in history?
Let's give it a shot.
The world's rarest fish has been stolen from the city aquarium.
The police have followed the scent to a street with five identical looking houses.
But they can't search all the houses at once, and if they pick the wrong one, the thief will know they're on his trail.
It's up to you, the city's best detective, to solve the case.
When you arrive on the scene, the police tell you what they know.
One: each house's owner is of a different nationality, drinks a different beverage, and smokes a different type of cigar.
Two: each house's interior walls are painted a different color.
Three: each house contains a different animal, one of which is the fish.
After a few hours of expert sleuthing, you gather some clues.
It may look like a lot of information, but there's a clear logical path to the solution.
Solving the puzzle will be a lot like Sudoku, so you may find it helpful to organize your information in a grid, like this.
Pause the video on the following screen to examine your clues and solve the riddle.
Answer in: 3 2 1 To start, you fill in the information from clues eight and nine.
Immediately, you also realize that since the Norwegian is at the end of the street, there's only one house next to him, which must be the one with the blue walls in clue fourteen.
Clue five says the green-walled house's owner drinks coffee.
It can't be the center house since you already know its owner drinks milk, but it also can't be the second house, which you know has blue walls.
And since clue four says the green-walled house must be directly to the left of the white-walled one, it can't be the first or fifth house either.
The only place left for the green-walled house with the coffee drinker is the fourth spot, meaning the white-walled house is the fifth.
Clue one gives you a nationality and a color.
Since the only column missing both these values is the center one, this must be the Brit's red-walled home.
Now that the only unassigned wall color is yellow, this must be applied to the first house, where clue seven says the Dunhill smoker lives.
And clue eleven tells you that the owner of the horse is next door, which can only be the second house.
The next step is to figure out what the Norwegian in the first house drinks.
It can't be tea, clue three tells you that's the Dane.
As per clue twelve, it can't be root beer since that person smokes Bluemaster, and since you already assigned milk and coffee, it must be water.
From clue fifteen, you know that the Norwegian's neighbor, who can only be in the second house, smokes Blends.
Now that the only spot in the grid without a cigar and a drink is in the fifth column, that must be the home of the person in clue twelve.
And since this leaves only the second house without a drink, the tea-drinking Dane must live there.
The fourth house is now the only one missing a nationality and a cigar brand, so the Prince-smoking German from clue thirteen must live there.
Through elimination, you can conclude that the Brit smokes Pall Mall and the Swede lives in the fifth house, while clue six and clue two tell you that these two have a bird and a dog, respectively.
Clue ten tells you that the cat owner lives next to the Blend-smoking Dane, putting him in the first house.
Now with only one spot left on the grid, you know that the German in the green-walled house must be the culprit.
You and the police burst into the house, catching the thief fish-handed.
While that explanation was straightforward, solving puzzles like this often involves false starts and dead ends.
Part of the trick is to use the process of elimination and lots of trial and error to hone in on the right pieces, and the more logic puzzles you solve, the better your intuition will be for when and where there's enough information to make your deductions.
And did young Einstein really write this puzzle?
Probably not.
There's no evidence he did, and some of the brands mentioned are too recent.
But the logic here is not so different from what you'd use to solve equations with multiple variables, even those describing the nature of the universe.
Evidence suggests that humans in all ages and from all cultures create their identity in some kind of narrative form.
From mother to daughter, preacher to congregant, teacher to pupil, storyteller to audience.
Whether in cave paintings or the latest uses of the Internet, human beings have always told their histories and truths through parable and fable.
We are inveterate storytellers.
But where, in our increasingly secular and fragmented world, do we offer communality of experience, unmediated by our own furious consumerism?
And what narrative, what history, what identity, what moral code are we imparting to our young?
Cinema is arguably the 20th century's most influential art form.
Its artists told stories across national boundaries, in as many languages, genres and philosophies as one can imagine.
Indeed, it is hard to find a subject that film has yet to tackle.
During the last decade we've seen a vast integration of global media, now dominated by a culture of the Hollywood blockbuster.
We are increasingly offered a diet in which sensation, not story, is king.
What was common to us all 40 years ago -- the telling of stories between generations -- is now rarified.
As a filmmaker, it worried me.
As a human being, it puts the fear of God in me.
What future could the young build with so little grasp of where they've come from and so few narratives of what's possible?
The irony is palpable; technical access has never been greater, cultural access never weaker.
And so in 2006 we set up FILMCLUB, an organization that ran weekly film screenings in schools followed by discussions.
If we could raid the annals of 100 years of film, maybe we could build a narrative that would deliver meaning to the fragmented and restless world of the young.
Given the access to technology, even a school in a tiny rural hamlet could project a DVD onto a white board.
In the first nine months we ran 25 clubs across the U.K., with kids in age groups between five and 18 watching a film uninterrupted for 90 minutes.
The films were curated and contextualized.
But the choice was theirs, and our audience quickly grew to choose the richest and most varied diet that we could provide.
The outcome, immediate.
It was an education of the most profound and transformative kind.
In groups as large as 150 and as small as three, these young people discovered new places, new thoughts, new perspectives.
By the time the pilot had finished, we had the names of a thousand schools that wished to join.
The film that changed my life is a 1951 film by Vittorio De Sica, "Miracle in Milan."
It's a remarkable comment on slums, poverty and aspiration.
I had seen the film on the occasion of my father's 50th birthday.
Technology then meant we had to hire a viewing cinema, find and pay for the print and the projectionist.
But for my father, the emotional and artistic importance of De Sica's vision was so great that he chose to celebrate his half-century with his three teenage children and 30 of their friends, "In order," he said, "to pass the baton of concern and hope on to the next generation."
In the last shot of "Miracle in Milan," slum-dwellers float skyward on flying brooms.
Sixty years after the film was made and 30 years after I first saw it, I see young faces tilt up in awe, their incredulity matching mine.
And the speed with which they associate it with "Slumdog Millionaire" or the favelas in Rio speaks to the enduring nature.
In a FILMCLUB season about democracy and government, we screened "Mr. Smith Goes to Washington."
Made in 1939, the film is older than most of our members' grandparents.
Frank Capra's classic values independence and propriety.
It shows how to do right, how to be heroically awkward.
It is also an expression of faith in the political machine as a force of honor.
Shortly after "Mr. Smith" became a FILMCLUB classic, there was a week of all-night filibustering in the House of Lords.
And it was with great delight that we found young people up and down the country explaining with authority what filibustering was and why the Lords might defy their bedtime on a point of principle.
After all, Jimmy Stewart filibustered for two entire reels.
In choosing "Hotel Rwanda," they explored genocide of the most brutal kind.
It provoked tears as well as incisive questions about unarmed peace-keeping forces and the double-dealing of a Western society that picks its moral fights with commodities in mind.
And when "Schindler's List" demanded that they never forget, one child, full of the pain of consciousness, remarked, "We already forgot, otherwise how did 'Hotel Rwanda' happen?"
As they watch more films their lives got palpably richer.
"Pickpocket" started a debate about criminality disenfranchisement.
"To Sir, with Love" ignited its teen audience.
They celebrated a change in attitude towards non-white Britons, but railed against our restless school system that does not value collective identity, unlike that offered by Sidney Poitier's careful tutelage.
By now, these thoughtful, opinionated, curious young people thought nothing of tackling films of all forms -- black and white, subtitled, documentary, non-narrative, fantasy -- and thought nothing of writing detailed reviews that competed to favor one film over another in passionate and increasingly sophisticated prose.
Six thousand reviews each school week vying for the honor of being review of the week.
From 25 clubs, we became hundreds, then thousands, until we were nearly a quarter of a million kids in 7,000 clubs right across the country.
And although the numbers were, and continue to be, extraordinary, what became more extraordinary was how the experience of critical and curious questioning translated into life.
Some of our kids started talking with their parents, others with their teachers, or with their friends.
And those without friends started making them.
The films provided communality across all manner of divide.
And the stories they held provided a shared experience.
"Persepolis" brought a daughter closer to her Iranian mother, and "Jaws" became the way in which one young boy was able to articulate the fear he'd experienced in flight from violence that killed first his father then his mother, the latter thrown overboard on a boat journey.
Who was right, who wrong?
What would they do under the same conditions?
Was the tale told well?
Was there a hidden message?
How has the world changed?
How could it be different?
A tsunami of questions flew out of the mouths of children who the world didn't think were interested.
And they themselves had not known they cared.
And as they wrote and debated, rather than seeing the films as artifacts, they began to see themselves.
I have an aunt who is a wonderful storyteller.
In a moment she can invoke images of running barefoot on Table Mountain and playing cops and robbers.
Quite recently she told me that in 1948, two of her sisters and my father traveled on a boat to Israel without my grandparents.
When the sailors mutinied at sea in a demand for humane conditions, it was these teenagers that fed the crew.
I was past 40 when my father died.
He never mentioned that journey.
My mother's mother left Europe in a hurry without her husband, but with her three-year-old daughter and diamonds sewn into the hem of her skirt.
After two years in hiding, my grandfather appeared in London.
He was never right again.
And his story was hushed as he assimilated.
My story started in England with a clean slate and the silence of immigrant parents.
I had "Anne Frank," "The Great Escape," "Shoah," "Triumph of the Will."
It was Leni Riefenstahl in her elegant Nazi propaganda who gave context to what the family had to endure.
These films held what was too hurtful to say out loud, and they became more useful to me than the whispers of survivors and the occasional glimpse of a tattoo on a maiden aunt's wrist.
Purists may feel that fiction dissipates the quest of real human understanding, that film is too crude to tell a complex and detailed history, or that filmmakers always serve drama over truth.
But within the reels lie purpose and meaning.
As one 12-year-old said after watching "Wizard of Oz," "Every person should watch this, because unless you do you may not know that you too have a heart."
We honor reading, why not honor watching with the same passion?
Consider "Citizen Kane" as valuable as Jane Austen.
Agree that "Boyz n the Hood," like Tennyson, offers an emotional landscape and a heightened understanding that work together.
Each a piece of memorable art, each a brick in the wall of who we are.
And it's okay if we remember Tom Hanks better than astronaut Jim Lovell or have Ben Kingsley's face superimposed onto that of Gandhi's.
And though not real, Eve Harrington, Howard Beale, Mildred Pierce are an opportunity to discover what it is to be human, and no less helpful to understanding our life and times as Shakespeare is in illuminating the world of Elizabethan England.
We guessed that film, whose stories are a meeting place of drama, music, literature and human experience, would engage and inspire the young people participating in FILMCLUB.
What we could not have foreseen was the measurable improvements in behavior, confidence and academic achievement.
Once-reluctant students now race to school, talk to their teachers, fight, not on the playground, but to choose next week's film -- young people who have found self-definition, ambition and an appetite for education and social engagement from the stories they have witnessed.
Our members defy the binary description of how we so often describe our young.
They are neither feral nor myopically self-absorbed.
They are, like other young people, negotiating a world with infinite choice, but little culture of how to find meaningful experience.
We appeared surprised at the behaviors of those who define themselves by the size of the tick on their shoes, yet acquisition has been the narrative we have offered.
If we want different values we have to tell a different story, a story that understands that an individual narrative is an essential component of a person's identity, that a collective narrative is an essential component of a cultural identity, and without it it is impossible to imagine yourself as part of a group.
Because when these people get home after a screening of "Rear Window" and raise their gaze to the building next door, they have the tools to wonder who, apart from them, is out there and what is their story.
Thank you.
(Applause)