Charles Petzold



The Lesser-Read George Eliot

November 22, 2019
Sayreville, N.J.

Today is the 200th anniversary of the birth of George Eliot, and I thought I’d celebrate by reading the more obscure books of hers that I’ve been neglecting over the years. In other words: I’ve read the best, now read the rest.

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Murder by Rifle vs. Death by Meteor

October 16, 2019
Sayreville, N.J.

What is it about gun advocates and math? Are the deceptions deliberate? Or does the excitement of grasping a sleek stiff tool in one’s hand cause a depletion of cognitive coherence?

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Clever Cosmogonies of the 17th Century

October 8, 2019
Sayreville, NJ

In 1700, almost everybody in Europe believed that the earth was about six thousand years old. That’s the approximate timeframe derived from chronologies in the Old Testament beginning with the description of Creation in the book of Genesis. It’s not exact. The author of one 18th century book on sacred history collected over 200 different estimates of the date of Creation ranging from 3483 BC to 6984 BC.

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The Racism of the Electoral College, Mathematically Demonstrated

August 26, 2019
Roscoe, NY

Representative Alexandria Ocasio-Cortez recently suggested that the Electoral College is racist. Obviously Fox News objected to that characterization, and even one of my Facebook friends linked to the article and called Ms. Ocasio-Cortez a "dimwit."

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“Computer of the Tides” Chapter 4 Outtake

June 6, 2019
Roscoe, NY

When did the world get to be so old? In Newton's time, the world was assumed to be about six thousand years old, but by the time of Darwin's Origin of Species, it had become millions and billions of years old. When did this happen?

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Reading Ian McEwan’s “Machines Like Me”

April 26, 2019
Sayreville, New Jersey

It is 1982, and England has just suffered a devastating defeat in the Falklands War. Argentina had managed to obtain some Exocet Series 8 missiles equipped with A.I. targeting software that inflicted enormous damage on Britain’s warships and left almost 3,000 dead. This software, however, had an innocent origin: It was based on open-source facial-recognition algorithms that Alan Turing had designed in the 1960s to help people with the face-blindness condition known as prosopagnosia.

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Reading “Stoner” by John Williams

April 22, 2019
Sayreville, New Jersey

After reading several articles about “the best novel you’ve never heard of,” I finally surrendered and determined for myself the cause of this unadulterated acclaim. The title of this novel is peculiar: Although John Williams’ Stoner was published in 1965, the title refers not to a hippie drug addict but to the staid and stern William Stoner, who for four decades teaches English at the University of Missouri.

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Reading “Sounds Like Titanic”

April 7, 2019
Sayreville, New Jersey

Jessica Chiccehitto Hindman is four years old when she first hears the music that makes her want to play the violin. It was an animated film called Sarah and the Squirrel about a young girl escaping the Holocaust, accompanied by music the likes of which she had never heard. “Violin music,” her father tells her, and from that moment on, she wants to play that music. Much later she will learn that the music in the movie is the opening of the Winter concerto from Vivaldi’s Four Seasons, and chills go up my spine just imagining a four-year-old hearing that music for the very first time.

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Reflections on Rereading “Slaughterhouse-Five”

March 31, 2019
Sayreville, New Jersey

Kurt Vonnegut’s novel Slaughterhouse-Five or The Children’s Crusade: A Duty Dance with Death was published 50 years ago today, as I was informed by several articles, including this one and this one in the New York Times. Fortunately, I rarely dispose of books that I’ve bought, so I was able to pluck the $1.95 paperback off my shelf and read it again, probably for the first time since my college years in the early 1970s. (Check your own bookshelves; you might find a copy as well.)

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Haydn and Herschel in the Clair de Lune

March 25, 2019
Sayreville, New Jersey

It was a meeting of minds so great that if it didn’t really happen, it would be necessary to make it up. On June 15, 1792, Joseph Haydn, the most famous composer in Europe, journeyed to Slough, England, to the home and astronomical observatory of William and Caroline Herschel. As Richard Holmes wrote in his marvelous history The Age of Wonder: How the Romantic Generation Discovered the Beauty and Terror of Science (NY: HarperCollins, 2008), “Visits to his observatory were regarded as uplifting, even religious experiences. Joseph Haydn claimed that his visit to Herschel at Slough in 1798 [actually 1792] had helped him compose his oratorio The Creation.” (page 199)

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π Does Not Exist

3.14 Day 2019
Sayreville, New Jersey

The thing we call π is the ratio of the circumference of an ideal circle to its diameter, but the word “ideal” here means “existing only in the mind.” Perfect circles can’t exist in the real world.

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Biblical Chronology and the Encyclopædia Britannica

March 4, 2019
Sayreville, New Jersey

Encyclopedias are probably not the best barometers of social and intellectual change, but I thought it might be interesting to track how the Encyclopædia Britannica adapted over time in treating Biblical chronology and specifically, the date of the creation of the world. At one time, the Encyclopædia Britannica said that the world was created around 4000 B.C., and then it did not. When did this change occur?

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Reading “Wayward Lives, Beautiful Experiments”

February 27, 2019
Sayreville, New Jersey

This is a work of history in which startling acts of resurrection take place: Poor young African-American women in Philadelphia and New York City in the late 19th and early 20th centuries engaged in the most ordinary of activities — walking down the street looking in shop windows, hanging out with friends on the street or hallways, going to clubs and music halls, striving to be singers or dancers — emerge to become extraordinary vivid living exemplars and experimenters of 20th century life.

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Reading “Frederick Douglass: Prophet of Freedom”

February 25, 2019
Rev. Feb. 26, 2019
Sayreville, New Jersey

The outlines of Frederick Douglass’s story are known to everyone who has even the slightest knowledge of American history: How Douglass was born into slavery but escaped to become the most prominent abolitionist of his time, both writing and speaking with great power and moral authority.

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James Earl Jones Saves the Play

February 8, 2019
Sayreville, New Jersey

When I was 15 years old, my mother started letting me take the bus into New York City by myself. I would walk to the bus stop at the intersection of Route 9 and Ernston Road (at that time a traffic light), and after a 45-minute bus trip arrive at the Port Authority Bus Terminal. Usually I just went to bookstores but sometimes I saw a play, and that’s how I saw James Earl Jones onstage in The Great White Hope, and witnessed the great actor improvising a save when something unexpected threatened to blunt the play’s impact.

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Reading “Little Dancer Aged Fourteen”

January 30, 2019
Sayreville, New Jersey

I've always been both fascinated and disturbed by Degas' paintings of young ballerinas. The tutus are so frilly, the legs and arms exquisitely posed even when they're not dancing, but the faces are often turned away from us, and when we do see their faces, they are deliberately smudged, or appear pained, weary, and exhausted, so unlike the radiant faces of Renoir's young women. There may be beauty in the ballerinas' poses and movement, but no joy in their execution. Rarely do we glimpse a smile.

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Reading “Diderot and the Art of Thinking Freely”

January 28, 2019
Sayreville, New Jersey

Denis Diderot (1713 - 1784) is best known as editor and frequent contributor to the Encyclopédie that defined many of the goals and ideas of the French Enlightenment. He wrote novels as well, but they're very strange -- elliptical, digressive, and satirical dialogues that hover somewhere between fictional fantasies and philosophical tracts. Consequently, it's hard to get a grasp on the main thrust of his ideas.

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“All the Books of Moses / Were nothing but supposes”

January 26, 2019
Sayreville, New Jersey

The wittily rhyming couplet that titles this blog entry originated in England around the year 1695, a time when such flippant irreverence is not expected. This was an era of orthodox piety: The sovereigns (William and the recently desceased Mary) were of a stern Calvinistic disposition; neither Isaac Newton nor John Locke (two of England's greatest minds of this decade) questioned the authenticity of the Biblical narrative of Creation; Voltaire was but an infant; and in America, the Salem witch trials had just ended.

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Reading “Ada Lovelace: The Making of a Computer Scientist”

January 24, 2019
Sayreville, New Jersey

A recent TV commercial for a pizza delivery chain shows a father electronically summoning his family to dinner when the pizza arrives. The kids drop what they’re doing and rush home. The man’s wife is teaching a college chemistry class when she gets the notification. She quickly gathers up her belongings and hurries out of the classroom, telling the class “You're never gonna use this anyway.”

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Reading “Bringing Down the Colonel”

January 21, 2019
Sayreville, New Jersey

At first, Bringing Down the Colonel seems like a retelling of a tawdry sex scandal of the 1890s, but in Patricia Miller's skillful hands, it becomes a springboard for a panoramic view of the burgeoning feminist movement in the decades prior to the 20th century.

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Retirement and Realignment

September 14, 2018
Sayreville, New Jersey

Effective today, I have resigned my employment at Microsoft, concluding an engaging and delightful 4½ years as part of the Xamarin documentation team. I will miss my co-workers immensely, and I hope to keep in touch with them on Facebook.

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“Computer of the Tides” – The Chapter 2 Schematic

May 7, 2017
New York, NY

In the original 1988 edition of his book A Brief History of Time, Stephen Hawking famously revealed why the book contains virtually no mathematics:

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The Dawn of the Sinusoid

April 8, 2017
Roscoe, NY

I’ve been thinking about sine curves recently. The gently undulating pattern of the sinusoid is one of the most familiar mathematical images, but how long has that been the case? Who were the first people to see this curve? Who was the first person to draw it?

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“Computer of the Tides” Chapter 1 (Draft Preview)

December 29, 2016
New York, N.Y.

For over a decade, I’ve been poking away at a book I call Computer of the Tides: Lord Kelvin’s Machine to Disprove Evolution, an extended history of an early analog computer invented by Scottish scientist William Thomson (Lord Kelvin), and its role in the 19th century Darwin Wars.

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Reading Steve Pincus’s “The Heart of the Declaration”

October 30, 2016
New York, N.Y.

I loved Yale historian Steve Pincus’s monumental book 1688: The First Modern Revolution (Yale University Press, 2011). It’s not exactly a primer on the Glorious Revolution; for that purpose, I think a more conventional narrative account such as Tim Harris’s Revolution: The Great Crisis of the British Monarchy, 1685-1720 might be better. But reading Pincus is essential when you think you know the Glorious Revolution and want a fresh look that goes much deeper.

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Reading Margot Lee Shetterly’s “Hidden Figures”

September 19, 2016
New York, N.Y.

For a few optimistic years at the beginning of the 20th century, some people believed that the invention of the airplane had effectively ended war. Air warfare was potentially so horrible and so destructive that no country would dare start a war that might make use of airplanes to invade and bomb from the sky.

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The Metric System for Angles and Time

June 5, 2016
Roscoe, N.Y.

“I often say that when you can measure what you are speaking about and express it in numbers you know something about it; but when you cannot measure it, when you cannot express it in numbers, your knowledge is of a meagre and unsatisfactory kind: it may be the beginning of knowledge, but you have scarcely, in your thoughts, advanced to the stage of science, whatever the matter may be.” — William Thomson (Lord Kelvin), 1883.

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