When is Cheryl's Birthday? Question and answer from Sal Khan of Khan Academy

April 17, 2015 Philip Waring Leave a comment

A TV presenter in Singapore recently referred to a math problem that has been driving the Internet crazy.

The problem may at first seem impossible to solve, but once you use some logic, the solution is actually rather simple.

Try it yourself before listening to Sal’s explanation on the video.

The question was originally thought to be posed to fifth graders but was later clarified to be for 14-year-olds competing in the Singapore and Asean Schools Math Olympiads (SASMO).

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LAST DAY IN FORCALQUIER, HAUTE PROVENCE

This Blogger

Am retired. With my wife Josée I Iive in Tampa, and go often to Paris. There’s not yet a land bridge between the two cities so to go back and forth we fly, in the dead of night on the way over, and in the light of early and late afternoon on the way back.
Tampa, I believe, is America, the best and the worst of it, mostly the best. And Paris, well, Paris is Paris, not yet a museum, but almost.

What he does or What he thinks

“There is no human nature; man is what he does.” Jean-Paul Sartre

“A man is but a product of his thoughts. What he thinks he becomes.” – Mahatma Gandhi

Maria Popova, Bulgarian Writer

I live in Tampa

4200 W Santiago St.
Tampa, Fl 33629

I used to live in Paris

Rue des Fossés St. Bernard
Paris, France 75005

Albert Einstein once said —

there are only two things that might be infinite: the universe and human stupidity.

And, he confessed, he wasn’t sure about the universe.

1905 — HG Wells — The plain message physical science has for the world at large is this, that were our political and social and moral devices only as well contrived to their ends as a linotype machine, an antiseptic operating plant, or an electric tram-car, there need now at the present moment be no appreciable toil in the world, and only the smallest fraction of the pain, the fear, and the anxiety that now makes human life so doubtful in its value. There is more than enough for everyone alive. Science stands, a too competent servant, behind her wrangling underbred masters, holding out resources, devices, and remedies they are too stupid to use.

1932 — Charles Beard begins his introduction to J.B.Bury's The Idea of Progress by observing that "the world is largely ruled by ideas, true and false.'

1957 — Ludwig von Mises "The genuine history of mankind is the history of ideas. It is ideas that distinguish man from all other beings. For it is ideas, theories, and doctrines that guide human action, determine the ultimate ends men aim at, and the choice of the means employed for the attainment of these ends.

Horace Mann et al.

“There can be no greater stretch of arbitrary power than is required to seize children from their parents, teach them whatever the authorities decree they shall be taught, and expropriate from the parents the funds to pay for the procedure.”
from Isabel Paterson, author of The God of the Machine (1943)

Germany has supplied ample evidence that it is quite possible to read Rilke poems in the morning, play Beethoven at night, and shoot Jews during the day.

Roger Cohen, NYTimes, April 1, 2016

Hatred, fomented in the name of utopian illusion, returns. It is unbearable for some to accept Kant’s “crooked timber of humanity” out of which no straight thing was ever fashioned.
The essence of liberalism is acceptance of our human limits and our human differences. It is acceptance of multiple and perhaps incompatible truths.
In Europe and America, liberalism is threatened today. Anger rises. Bullies have workable material.

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Aristotle says that —

"To take no part in the running of the community's affairs is to be either a beast or a god!"

Well I take no part in the community's affairs, and I'm not a god, ...

The Passion of Liu Xiaobo, Perry Link in the July ’17 NYR

Liu, born in 1955, was eleven when Mao closed the schools, but he read books anyway, wherever he could find them. With no teachers to tell him what the government wanted him to think about what he read, he began to think for himself—and he loved it. Mao had inadvertently taught him a lesson that ran directly counter to Mao’s own goal of converting children into “little red soldiers.”

But this experience only partly explains Liu’s stout independence. It also seems to have been an inborn trait. If there is a gene for bluntness, Liu likely had it. In the 1980s, while still a graduate student in Chinese literature, he was already known as a “black horse” for denouncing nearly every contemporary Chinese writer: the literary star Wang Meng was politically slippery; “roots-seeking” writers like Han Shaogong were excessively romantic about the value of China’s traditions; even speak-for-the-people heroes like Liu Binyan were too ready to pin hopes on “liberal” Communist leaders like Hu Yaobang. No one was independent enough.

“I can sum up what’s wrong with Chinese writers in one sentence,” Liu Xiaobo wrote in 1986. “They can’t write creatively themselves—they simply don’t have the ability—because their very lives don’t belong to them.”

Evolution and Our Inner Conflict

By Edward O. Wilson
June 24, 2012

Are human beings intrinsically good but corruptible by the forces of evil, or the reverse, innately sinful yet redeemable by the forces of good? Are we built to pledge our lives to a group, even to the risk of death, or the opposite, built to place ourselves and our families above all else? Scientific evidence, a good part of it accumulated during the past 20 years, suggests that we are all of these things simultaneously. Each of us is inherently complicated. We are all genetic chimeras, at once saints and sinners — not because humanity has failed to reach some foreordained religious or ideological ideal — but because of the way our species originated across millions of years of biological evolution.
Kin selection alone doesn’t adequately explain our complex natures.

Don’t get me wrong. I am not implying that we are driven by instinct in the manner of animals. Yet in order to understand the human condition, it is necessary to accept that we do have instincts, and will be wise to take into account our very distant ancestors, as far back and in as fine a detail as possible. History is not enough to reach this level of understanding. It stops at the dawn of literacy, where it turns the rest of the story over to the detective work of archaeology; in still deeper time the quest becomes paleontology. For the real human story, history makes no sense without prehistory, and prehistory makes no sense without biology. Within biology itself, the key to the mystery is the force that lifted pre-human social behavior to the human level. The leading candidate in my judgment is multilevel selection by which hereditary social behavior improves the competitive ability not of just individuals within groups but among groups as a whole. Its consequences can be plainly seen in the caste systems of ants, termites and other social insects. Between-group selection as a force operating in addition to between-individual selection simultaneously is not a new idea in biology. Charles Darwin correctly deduced its role, first in the insects and then in human beings — respectively in “On the Origin of Species” and “The Descent of Man.”
Even so, the reader should be warned that the revival of multilevel selection as the principal force of social evolution remains a hotly contested idea. Its opponents believe the principal force to be kin selection: when individuals favor kin (other than offspring), the evolution of altruistic behavior is favored. The loss suffered by the genes of the altruist are compensated by genes in the recipient made identical by common descent of the altruist and recipient. If the altruism thus created is strong enough it can lead to advanced social behavior. This seems plausible, but in 2010 two mathematical biologists, Martin Nowak and Corina Tarnita, and I demonstrated that the mathematical foundations of the kin selection theory are unsound, and that examples from nature thought to support kin selection theory are better explained as products of multilevel selection.

A strong reaction from supporters of kin selection not surprisingly ensued, and soon afterward more than 130 of them famously signed on to protest our replacement of kin selection by multilevel selection, and most emphatically the key role given to group selection. But at no time have our mathematical and empirical arguments been refuted or even seriously challenged. Since that protest, the number of supporters of the multilevel selection approach has grown, to the extent that a similarly long list of signatories could be obtained. But such exercises are futile: science is not advanced by polling. If it were, we would still be releasing phlogiston to burn logs and navigating the sky with geocentric maps.

I am convinced after years of research on the subject that multilevel selection, with a powerful role of group-to-group competition, has forged advanced social behavior — including that of humans, as I documented in my recent book “The Social Conquest of Earth.”

In fact, it seems clear that so deeply ingrained are the evolutionary products of group selected behaviors, so completely a part of the human condition, that we are prone to regard them as fixtures of nature, like air and water. They are instead idiosyncratic traits of our species. Among them is the intense, obsessive interest of people in other people, which begins in the first days of life as infants learn particular scents and sounds of the adults around them. Research psychologists have found that all normal humans are geniuses at reading the intentions of others, whereby they evaluate, gossip, proselytize, bond, cooperate and control. Each person, working his way back and forth through his social network, almost continuously reviews past experiences while imagining the consequences of future scenarios.

A second diagnostic hereditary peculiarity of human behavior is the overpowering instinctual urge to belong to groups in the first place. To be kept in solitude is to be kept in pain, and put on the road to madness. A person’s membership in his group — his tribe — is a large part of his identity. It also confers upon him to some degree or other a sense of superiority. When psychologists selected teams at random from a population of volunteers to compete in simple games, members of each team soon came to think of members of other teams as less able and trustworthy, even when the participants knew they had been selected at random.

All things being equal (fortunately things are seldom equal, not exactly), people prefer to be with others who look like them, speak the same dialect, and hold the same beliefs An amplification of this evidently inborn predisposition leads with frightening ease to racism and religious bigotry.

It might be supposed that the human condition is so distinctive and came so late in the history of life on Earth as to suggest the hand of a divine creator. Yet in a critical sense the human achievement was not unique at all. Biologists have identified about two dozen evolutionary lines in the modern world fauna that attained advanced social life based on some degree of altruistic division of labor. Most arose in the insects. Several were independent origins, in marine shrimp, and three appeared among the mammals, that is, in two African mole rats, and us. All reached this level through the same narrow gateway: solitary individuals, or mated pairs, or small groups of individuals built nests and foraged from the nest for food with which they progressively raised their offspring to maturity.

Until about three million years ago the ancestors of Homo sapiens were mostly vegetarians, and they most likely wandered in groups from site to site where fruit, tubers, and other vegetable food could be harvested. Their brains were only slightly larger than those of modern chimpanzees. By no later than half a million years ago, however, groups of the ancestral species Homo erectus were maintaining campsites with controlled fire — the equivalent of nests — from which they foraged and returned with food, including a substantial portion of meat. Their brain size had increased to midsize, between that of chimpanzees and modern Homo sapiens. The trend appears to have begun one to two million years previously, when the earlier prehuman ancestor Homo habilis turned increasingly to meat in its diet. With groups crowded together at a single site, and an advantage added by cooperative nest building and hunting, social intelligence grew, along with the centers of memory and reasoning in the prefrontal cortex.

Probably at this point, during the habiline period, a conflict ensued between individual-level selection, with individuals competing with other individuals in the same group, versus group-level selection, with competition among groups. The latter force promoted altruism and cooperation among all the group members. It led to group-wide morality and a sense of conscience and honor. The competitor between the two forces can be succinctly expressed as follows: within groups selfish individuals beat altruistic individuals, but groups of altruists beat groups of selfish individuals. Or, risking oversimplification, individual selection promoted sin, while group selection promoted virtue.
So it appeared that humans are forever conflicted by their prehistory of multilevel selection. They are suspended in unstable and constantly changing locations between the two extreme forces that created us. We are unlikely to yield completely to either force as an ideal solution to our social and political turmoil. To yield completely to the instinctual urgings born from individual selection would dissolve society. To surrender to the urgings from group selection would turn us into angelic robots — students of insects call them ants.

The eternal conflict is not God’s test of humanity. It is not a machination of Satan. It is just the way things worked out. It might be the only way in the entire universe that human-level intelligence and social organization can evolve. We will find a way eventually to live with our inborn turmoil, and perhaps find pleasure in viewing it as a primary source of our creativity.

A walk on the beach

Josée Delcroix, Drawing, Paris 1954

The Constitution and its Articles were adopted into the United States on September 17, 1787 during the Constitutional Convention in Philadelphia.

The Articles of The Constitution work to establish the branches of the federal government and describe what powers they have.

Article 1 gives Congress its powers and limits. Congress is the branch of the government who can make laws for the country. Article 1 also creates the two sections of Congress, the Senate and the House of Representatives.

Article 2 makes the executive branch of the government. The Executive branch has the responsibility and authority for the administration on a daily basis. In the United States, the executive branch is made up of the President and executive officer

Article 3 creates a judicial branch in the United States. The Judicial branch is the court system that interprets the law. In the United States, the judicial branch includes the Supreme Court and the lower courts which are made by Congress.

Article 4 talks about the states. Article 4 talks about what responsibilities and duties the states have along with what responsibilities the federal government has to each States.

Article 5 says that the only way the Constitution can be changed is by adding an amendment.

Article 6 says that any debts or engagements that the country had before adopting the Constitution are still valid. Article 6 also says that the Constitution is the highest law and that all officers and judges have to uphold the Constitution.

Article 7 is the final article of the Constitution. This article explains how many states need to ratify the Constitution.

The Cosmos as seen from an observatory in Hawaii.

The map shows roughly 800 million stars in the neighborhood of the Milky Way. At first, it looks like a planet: dark, snow-speckled and slashed down the center by a deep red scar. But zoom in a little closer, and you realize you’re looking at something much larger than a planet — larger even than 100 billion planets. Hidden within this mosaic image of the Milky Way (that’s the big, red smear in the middle) and its near cosmic neighborhood are the more than 800 million stars, galaxies and roving interstellar objects visible from the Pan-STARRS mountaintop observatory in Maui, Hawaii.

It is one of the most remarkable things that in all of the biological sciences there is no clue as to the necessity of death. And because everyone has always died, we live under the “death and taxes” assumption that death is inevitable. We think of aging like time—both keep moving and there’s nothing you can do to stop them. But that assumption is wrong. If you say we want to make perpetual motion, we have discovered enough laws as we studied physics to see that it is either absolutely impossible or else the laws are wrong. But there is nothing in biology yet found that indicates the inevitability of death. This suggests to me that it is not at all inevitable and that it is only a matter of time before the biologists discover what it is that is causing us the trouble and that this terrible universal disease or temporariness of the human’s body will be cured. The fact is, aging isn’t stuck to time. Time will continue moving, but aging doesn’t have to. If you think about it, it makes sense. All aging is is the physical materials of the body wearing down. A car wears down over time too—but is its aging inevitable? If you perfectly repaired or replaced a car’s parts whenever one of them began to wear down, the car would run forever. The human body isn’t any different—just far more complex. —Richard Feynman

The Free Trade of Ideas

Justice Oliver Wendell Holmes’s 1919 dissenting opinion in Abrams v. United States :. “The ultimate good desired is better reached by free trade in ideas,” he wrote. “The best test of truth is the power of the thought to get itself accepted in the competition of the market.” The corrupt information that dominates the private square does not rise to the top of a free and fair competition of ideas. It wins in a rigged game. No democracy can survive this game.

Hokusai, Japanese Artist, (1760 – 1849)

In a postscript to his work, Hokusai writes: “ From around the age of six, I had the habit of sketching from life. I became an artist, and from fifty on began producing works that won some reputation, but nothing I did before the age of seventy was worthy of attention. At seventy-three, I began to grasp the structures of birds and beasts, insects and fish, and of the way plants grow. If I go on trying, I will surely understand them still better by the time I am eighty-six, so that by ninety I will have penetrated to their essential nature. At one hundred, I may well have a positively divine understanding of them, while at one hundred and thirty, forty, or more I will have reached the stage where every dot and every stroke I paint will be alive. May Heaven, that grants long life, give me the chance to prove that this is no lie. ”

Free Trade in Ideas

Justice Oliver Wendell Holmes’s 1919 dissenting opinion in Abrams v. United States is a touchstone. “The ultimate good desired is better reached by free trade in ideas,” he wrote. “The best test of truth is the power of the thought to get itself accepted in the competition of the market.”

The United States, now a segregated class society.

I now believe that the United States is evolving into a segregated class society in which the remaining remnants of the original American project—limited government, free people running their own lives, communities solving their own problems—will soon have been lost altogether. Charles Murray. 10/15/2014

We’re just one among millions

There are thought to be somewhere between 5 million and 100 million species of plants and animals on Earth, of which 2 million have been identified. We're one of these.

Umberto Eco, If I were to rule the world

Men are religious animals. Dogs are not religious. It’s true they bark at the moon but it’s probably not because of religion. Humans have the tendency to search for the reason in their situations. There is a beautiful sentence attributed to GK Chesterton: “When men don’t believe in God any longer, it is not that they believe in nothing; they believe in everything.”
The ruler of the world can’t eliminate religion. You can be an atheist or a non-believer, but you have to recognise that the great majority of humans need some religious beliefs.

Prospect Magazine, December 2015

“Learn as if you were to live forever.” – Mahatma Gandhi

The Earth is Weeping

They came on horses and with guns, a martial culture overrunning a more peaceful one unprepared to meet the fight. It was a stunning and successful invasion over a short period of time. The invaders treated the indigenous people as barely human. They committed unspeakable acts of brutality. Those not massacred fled from their homeland, never to return. The invaders were the Lakota, a Siouxan tribe who swept west in the 1700s, taking for themselves the most prized hunting grounds throughout the Great Plains. Or, to put it in the words of one of their chiefs, “These lands once belonged to the Kiowas and Crows, but we whipped these nations out of them, and in this we did what the white men do when they want the lands of Indians.” Peter Cozzens, NR, 1/17

“Live as if you were to die tomorrow.” Mahatma Gandhi

‘DARWIN’S THEORY IS THE SINGLE GREATEST IDEA ANY HUMAN BEING HAS CONCEIVED, Daniel Dennett

Richard Rorty, Achieving Our Country, 1998

You have to describe the country in terms of what you passionately hope it will become, as well as in terms of what you know it to be now. You have to be loyal to a dream country rather than to the one to which you wake up every morning. Unless such loyalty exists, the ideal has no chance of becoming actual.

“now and then finding a smoother pebble or a prettier shell”

“I SEEM to have been only like a boy playing on the seashore, and diverting myself in now and then finding a smoother pebble or a prettier shell than ordinary, whilst the great ocean of truth lay all undiscovered before me.”

Those words, ascribed to Sir Isaac Newton, might still be spoken, with the appropriate correction for sex, by any scientist today.

The discipline of natural science that Newton helped found in the second half of the 17th century has extended humanity’s horizons to a degree he could scarcely have envisaged. Newton lived in a world that thought itself 6,000 years old, knew nothing of chemical elements or disease-causing microbes, believed living creatures could spring spontaneously from mud, hay or dirty bed-linen, and had only just stopped assuming that the sun (and everything else in the universe) revolved around the Earth.

Yet even today, deep problems and deeper mysteries remain. Science cannot yet say how life began or whether the universe is but one of many. Some things people take for granted—that time goes forwards but never backwards, say—are profoundly weird. Other mysteries, no less strange, are not even perceived. One is that 96% of the universe’s contents pass ghostlike and unnoticed through the minuscule remaining fraction, which solipsistic humans are pleased to call “ordinary matter”. Another is how, after billions of years when the Earth was inhabited only by single-celled creatures, animals suddenly popped into existence. Perhaps the deepest mystery of all is how atoms in human brains can consciously perceive the desire to ask all of these questions in the first place, and then move other atoms around to answer them.
The Economist, August 7, 2015

Anti-Intellectualism ion American Life

One of the major virtues of liberal society in the past was that it made possible such a variety of styles of intellectual life—one can find men notable for being passionate and rebellious, others for being elegant and sumptuous, or spare and astringent, clever and complex, patient and wise, and some equipped mainly to observe and endure. What matters is the openness and generosity needed to comprehend the varieties of excellence that could be found even in a single and rather parochial society. Dogmatic, apocalyptic predictions about the collapse of liberal culture or the disappearance of high culture may be right or wrong; but one thing about them seems certain: they are more likely to instill self-pity and despair than the will to resist or the confidence to make the most of one’s creative energies. It is possible, or course, that under modern conditions the avenues of choice are being closed, and that the culture of the future will be dominated by single-minded men of one persuasion or another. It is possible; but in so far as the weight of one’s will is thrown onto the scales of history, one lives in the belief that it is not to be so.
Richard Hofstadter, 1963

No Longer a Center-Right

Thomas Friedman would ask the candidates:
“Would you agree to raise the gasoline tax by 5 cents a gallon today so we can pay for our highway bill, now stalled in Congress over funding?”
Why, he asks, is this such a key question? And he answers because it cuts to the core of what is undermining the Republican Party today and, indirectly, our country: There is no longer a Republican center-right that would have no problem raising the gas tax for something as fundamental as infrastructure. Sure, there are center-right candidates — like Jeb Bush and John Kasich. But can they run, win and govern from the center-right when the base of their party and so many of its billionaire donors reflect the angry anti-science, anti-tax, anti-government, anti-minorities, anti-gay rights and anti-immigration views of the Tea Party and its media enforcer, Fox News? NYTimes, August 5, 2015

NATURAL SELECTION

The process whereby organisms better adapted to their environment tend to survive and produce more offspring.

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When is Cheryl's Birthday? Question and answer from Sal Khan of Khan Academy

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Liberté, Égalité, et Fraternité

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Liberté, Égalité, et Fraternité