Thursday, July 2, 2026

A Pearls Before Swine cartoon with advice in a pie chart from life coach Rat


 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

There is a Pearls Before Swine cartoon on July 1, 2026 by Stephan Pastis with the following dialogue:

 

Rat: I’m now a professional life coach, and because you’re my friend I’ve decided to help you for free.

 

Pig: Oh goodie! How?

Rat: It starts with this chart I’ve drawn up showing the percentage of your life that you act like a real dum dum.

 

Pig and Rat: looking at chart [see above]

 

Rat: Do that less.

 

Pig: Somehow your help never feels like help.

Rat: Shoot. Now it’s 99%.  

 

 

Monday, June 29, 2026

A collection from 1942 of The World’s Great Speeches


 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Sometimes we just run out of speech ideas, or suffer from writer’s block. At that point, we might want to get inspired by looking through a large collection of speeches. At the Internet Archive there is a pdf of a 748-page book titled The World’s Great Speeches, edited by Lewis Copeland. Contents are:

 

Part I: GREAT SPEECHES OF EARLIER TIMES

I.     Greece and Rome 

II.    The European Continent

III.   Great Britain and Ireland 

IV.   The United States 

V.    Canada 

VI.   South America, South Africa, India, and China 

 

Part II: GREAT SPEECHES OF OUR TIMES

VII.  American Industry and Government 

VIII. International Affairs 

IX.   The Second World War 

X.    National Defense

 

Part III: INFORMAL SPEECHES

XI.   Informal Speeches

 

Part IV: THE UNITED STATES AND THE SECOND WORLD WAR

XII.  The United States and the Second World War 12

 

TOPICAL INDEX

 

INDEX BY NATIONS

 

INDEX OF SPEAKERS

 

I created a cover using an image of fireworks modified from one at OpenClipArt. 

 

Sunday, June 28, 2026

Why did a keynote speaker overestimate his research skills?


 

 

 

 

 

 

 


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There is an article by John Eades at Learnloft on June 25, 2026 titled Why Most Leaders Overestimate Their Presentation Skills which opens by stating a startling ‘statistic’ that: 

“Fear is real, and there are a couple of common things people fear.

A survey revealed that people’s two biggest fears are public speaking and death.

Comedian Jerry Seinfeld landed a joke about the survey when he said, ‘Most people would rather be in the casket than giving the eulogy.’

It’s funny because it’s true. Most people despise the idea of public speaking.”

John did such superficial research that he confused a joke with a 1973 survey where death actually was seventh. Both are shown above. And that misquote is a paraphrase of what Jerry said in 1993. Back on April 8, 2018 I blogged about Misquoting Jerry Seinfeld and inflating fear five times.

 

He also has a 9-minute YouTube video at The Leadership Lens on June 25, 2026 titled Most Leaders Think They’re Good Presenters. They’re Not. Both the article and video have some useful content:

 

The Three Types of Presenters

 

Since leadership is more art than science, leaders can be introverted or extroverted. They are women and men. They are quiet and loud. However, after watching leaders across industries, most fall into one of three categories when presenting.

 

The Informer

The Informer knows their content cold. Their slides are detailed, their data is accurate, and their presentation is thorough. However, they confuse information transfer with communication. That doesn’t mean it’s bad, but it can be boring. The audience might even learn something. Their presentations are forgettable, not because they couldn’t be better or because their content is weak, but nothing makes it stick.  

 

The Rambler

The Rambler has real experience and genuine passion. When it lands, it’s magnetic. But without structure, the audience works too hard to follow. They leave inspired by the energy but unclear on the point. The Rambler’s biggest blind spot is thinking passion is enough. While it’s better than someone who doesn’t care, passion without structure is just noise with enthusiasm.

 

The Inspirer

The Inspirer knows their content and their audience. They don’t present at people, they present for them. They use story, tension, and intentional moments to connect ideas to emotions. They take chances by using authenticity to show their true self. The audience doesn’t just remember a few of the things they said – they remember how it made them feel.”

 

 

Thursday, June 25, 2026

On June 18, 2026 David Murray published his 4,493th post in the Writing Boots blog he started back in 2008


 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

David Murray edits the magazine Vital Speeches of the Day and runs the Professional Speechwriters Association. On June 18, 2026 he published his 4,493th post in the Writing Boots blog he had started back in 2008. It is titled Writing Boots: I Can’t Live With It, and I Can’t Live Without It. (I only have 3157 posts or ~70% of his total). I enjoy reading his blog, which he posts at almost every weekday (although Fridays usually are just a linked video).

 

He says he has used this blog:

 

"as a chance to sharpen my knives.

 

to remind myself, on muggy gray Tuesdays between magazine articles and books and other public stunts, that I exist.

 

to draw crowds by starting fights.

  

to be a self-righteous prick.

 

to write gentle poems that you wouldn’t read otherwise.

 

to make reading my thoughts, your habit.

 

to get things off by chest.

 

to settle scores.

 

to preen.

 

to figure out what I think.

 

to force myself to say something, every day.

 

to make saying something every day easy and natural. (It’s easier to write every day than once a week, a daily columnist and I agree).

 

To say whatever the fuck I want.

 

To keep from complaining that I’m not allowed to say whatever the fuck I want."

 

The writer image was cropped from Wikimedia Commons.

 

 

Tuesday, June 23, 2026

A claim about public speaking that wasn’t really in the 2023 Chapman Survey of American Fears


 

 

 

 

 

 

 

 

 

 

 

 

 

  

 

 

 

 

 

 

There is an article by Kathryn Janicek at LinkedIn Pulse on May 24, 2026 titled Your Body Is Sabotaging Your Speech Before You Say a Word. In her section titled The Part Nobody Prepares For she claimed:

 

“According to the Chapman University Survey of American Fears (2023), public speaking anxiety ranks among the most prevalent fears in American adults - above financial concerns and job loss for a significant portion of those surveyed.”

 

Why was she vague about the exact percentage and rank for the allegedly prevalent fear of public speaking? The survey has a web page with list of 97 fears ranked by percent. Public speaking was feared by 28.7% and only was ranked #53, which is not even in the upper half. There was not a question about financial concerns; Economic/financial collapse was #2 at 54.7% - far above public speaking. And there was not a question about job loss; Computers replacing people in the workforce was #47 at 31.6% and Being unemployed was #74 at 24.9%. On October 20, 2023 I blogged about how Corrupt government officials (60.1%) was the most common fear in the ninth 2023 Chapman Survey of American Fears. Public speaking was only ranked #53 (28.7%).

 

I also tried Google searching on the phrases “financial concerns” and “job loss” along with “Chapman survey” but came up empty.

 

But why didn’t she look at the most recent 2025 survey? On October 23, 2025 I blogged about how In the eleventh Chapman Survey of American Fears for 2025, public speaking was only ranked #46 of 67 fears at 33.7%.

 

 

Monday, June 22, 2026

Idaho’s Wassmuth Center for Human Rights celebrates its thirtieth anniversary


 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

An article by Valentin Termite at the Idaho Capital Sun on June 18, 2026 is titled Believing in the goodness of people: Idaho human rights center celebrates 30-year anniversary. It links to their web page on Wassmuth Powerful Practices, which briefly are titled (and then also explained in detail):

 

Collect Joy

Design for Belonging

Listen Deeply

Stay Curious

Notice and Name Bright Spots

Align Actions with Values

 

To collect joy you should:

 

“Notice, savor, and share moments of connection, warmth, and delight as expressions of human dignity and belonging. Paying attention to what is life-giving cultivates hope and sustains commitment to building a better world for all.” 

 

And, to listen deeply you should:

 

“Offer your full presence to another person without interruption, judgment, or trying to fix. Seeking to understand feelings, perspectives, and needs affirms that every person matters.” 

 

On October 27, 2024 I blogged about A new building at Boise’s Wassmuth Center for Human Rights with quotations carved in stone.

 

The border for the thirtieth came from OpenClipArt.

 

 

Saturday, June 20, 2026

Who is a pseudoexpert?


 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

There is a useful article by Joffrey Fuhrer et al. in Frontiers in Psychology on November 11, 2021 titled Pseudoexpertise: A Conceptual and Theoretical Analysis. Their abstract says:

 

“Some people publicly pretend to be experts while not being ones. They are pseudoexperts, and their presence seems to be ubiquitous in the current cultural landscape. This manuscript explores the nature and mechanisms of pseudoexpertise.

 

We first provide a conceptual analysis of pseudoexperts based on prototypical cases of pseudoexpertise and recent philosophical work on the concept of expertise. This allows us to propose a definition that captures real-world cases of pseudoexpertise, distinguishes it from related but different concepts such as pseudoscience, and highlights what is wrong with pseudoexpertise.

 

Next, based on this conceptual analysis, we propose a framework for further research on pseudoexpertise, built on relevant empirical and theoretical approaches to cultural cognition. We provide exploratory answers to three questions: why is there pseudoexpertise at all; how can pseudoexperts be successful despite not being experts; and what becomes of pseudoexperts in the long run. Together, these conceptual and theoretical approaches to pseudoexpertise draw a preliminary framework from which to approach the very troubling problem posed by persons usurping the capacities and reputations of genuine experts.”

 

I have discussed one well-known pseudoexpert in a post on October 7, 2025 titled Surrounded by bad books from Thomas Erikson. In that post I mentioned that:

 

“An article edited by Lotten Kalenius from the Swedish Skeptics Association (VoF) on April 15, 2024 is titled One of Sweden’s biggest scientific bluffs which discusses the book and Thomas Erikson. It has a section titled Is Erikson an authority in behavioural science? When he was looked up: 

 

‘So, we used Ladok, the register of everyone who has studied at Swedish colleges and university, to see if we could find the courses taken by Erikson. There was no-one with his name and birthdate registered. In fact, Erikson’s professional background is in sales, first for the bank Nordea and then running his own business training salespeople. It is most likely that his only educational background is, at best, the Swedish equivalent of a high school diploma.’ 

 

Lotten noted that Erikson was named Fraudster of the Year in 2018 by VoF and also added:

 

“He has as much right as my poodle to call himself a behavioural scientist.”

 

Guests on the Coast to Coast AM late-night radio show often are pseudoexperts who discuss their poorly researched books or videos.

 

The cartoon was adapted from the March 17, 1897 issue of Puck magazine at the Library of Congress.

 

 

Thursday, June 18, 2026

Polystyrene foam revealed by a demonstration


 

 

 

 

 

 

 

 

 

 

 

 


 

 

 

 

 

 

 

 

 

 

  

 

 

 


 

 

 

 

 

 

 

 

 

 

 

 

 

   

There is an interesting article by Joe Schwarcz at the McGill Office for Science and Society on June 9, 2026 titled The Case of the Missing Coffee Cup. He describes a demonstration:

 

“It is a demonstration that never fails to draw oohs and ahhs from students. Pour a small amount of acetone into the bottom of a beaker and drop in a foamed plastic coffee cup. It instantly seems to melt into the liquid and within seconds just vanishes.

Of course, matter cannot just vanish, but it can change from one form into another. Like sugar dissolving in water, the plastic dissolves in the acetone. How can so much plastic dissolve so quickly in so little acetone? Because there is actually very little plastic in that coffee cup.

Yet that little plastic has been expanded by being filled with gas bubbles, much like blowing up a balloon. As the plastic dissolves, the air is released, and we have an apparent magical effect.”

I repeated it using a cubical sample of polystyrene foam insulation placed in a glass custard cup as shown above. When acetone was added, it became just a small puddle. That got even smaller after the acetone evaporated.

A Wikipedia page for Polystyrene has a section on Expanded Polystyrene (EPS) – commonly known as Styrofoam.

 

 

 

 

Wednesday, June 17, 2026

Joy is the most enjoyable path to learning


 

 

 

 

 

 

 

 

 

 

 

There is a useful 2024 book by David Novak titled How Leaders Learn: Master the habits of the world’s most successful people. Google Books has a preview of its first sixty pages and six chapters.

 

On page 143 David says that:

 

Joy is our source of purpose, passion, mission – and the most enjoyable path to learning.

 

Of course, pursuing your joy requires that you know where to find it in your life and work. Not many people consider what makes them happiest, beyond things that aren’t necessarily within their control. When I wrote Take Charge of You with sports performance coach Jason Goldsmith, we tackled this question at the start. If you’re going to coach yourself to success, you need to know what you’re coaching yourself toward. We suggested people start by mining their experiences for joy blockers (we’re a bit better at remembering negatives) and then shift and search for their joy builders.

 

Try asking yourself this: What’s getting in the way of my joy? If you’re not sure, think back to some of your worst days, or a job that frustrated you or made you miserable or unfulfilled. What made it so difficult for you? Be as specific as possible. Did you want to be in a different role? Was there one specific thing that you were required to do that you dreaded doing? Was there a person or team you had to work with that brought you down?

 

I’m sure you can think of examples. We all hate our jobs sometimes. Even if you can think of examples, though, you may never have deeply reflected or logically analyzed why you were unhappy in a particular situation or environment.

 

I wish I could give a good example of this kind of reflection from my own life, but I’ve rarely felt that way. And I don’t think most active learners have much experience with it either, at least not for long. When active learners find themselves in a situation that’s too full of their joy blockers, they learn their way out of it or they learn their way around the blockers fast. They know if they don’t, they’ll stagnate. They also know that just because a job or situation doesn’t come preloaded with joy builders doesn’t mean it’s the wrong choice. It just means it’s up to them to find a way around the blockers.

 

….What are your joy builders? And how can you pursue them? Think about some of your best days or jobs – times when you felt especially purposeful, powerful, optimistic, and joyful. What was happening? What were you doing? Who were you doing it with? What specific things made you feel happy, excited, or energized? Try looking at your joy blocker examples and asking, What would have made me happier in those situations?”

 

My cartoon was assembled using a brick wall and stairs from OpenClipArt.  

 

 

Tuesday, June 16, 2026

Preaching by remixing or plagiarism?


 

 

 

 

 

 

 

 

 

 

 

I have been reading a 2026 book by David Epstein titled Inside the Box: How constraints make us better. At Google Books there is a preview up to page 23. He describes a different viewpoint about plagiarism in preaching. Chapter 6 is titled The Remix of Everything. Selected from pages 87 to 93, he says:

 

“Keith Miller was working on his English PhD at Texas Christian University in 1983, analyzing the rhetorical techniques in Martin Luther King Jr.’s sermons, when a friend alerted him to something strange.

 

The friend was studying at Vanderbilt University’s seminary, and had come across a 1968 King sermon –‘The Drum Major Instinct’ – that had a lot in common with a 1952 sermon (‘Drum Major Instincts’) by the prominent preacher J. Wallace Hamilton. Both use similar language to describe the human instinct to want to lead the parade and be recognized.

 

Miller assumed this was a one-off instance, until one day when he was perusing books in his father’s office. Rev. Ernest Miller was the head of a congregation in McAllen Texas, right along the border of Mexico, and he had a large library. Keith Miller was flipping through a text of old sermons when he landed on another with the same exact title as a sermon that King delivered later. It also used the same opening anecdote. Maybe ‘The Drum Major Instinct’ wasn’t an isolated instance after all.

 

Miller asked his father to list notable preachers. He took the list to the TCU seminary library and combed books of their sermons. Then he went to Atlanta to interview Martin Luther King Sr. and King’s mentor, Benjamin Mays, a minister and the former president of Morehouse College, from which King graduated at nineteen.

 

The more sermons Miller read, the more he realized he was rereading. He found shared titles, structures, anecdotes, and turns of phrase between King’s sermons and those of other preachers. Almost every sermon and essay of King’s he could find – even his Nobel Prize lecture – contained at least some historical antecedent. Sometimes it was the order of specific points, or common literary reference, or exact descriptions of a Biblical lesson. Sometimes it was all of the above. Take, for example, the sermon ‘What Is Man?’

 

….The more Miller read, the more tangled the web of influence and borrowing appeared to be. But he also found that King wasn’t unique; he was representative. Had Miller been a noir-film detective, his cork-board of evidence would have been completely obscured by red string connecting preachers and their sermons. King’s version was just the latest iteration in a deep ‘What Is Man?’ lineage.

 

….Keith Miller ended up writing not only a dissertation but a full book exhaustively tracing the source material of King’s sermons and essays; Voice of Deliverance: The Language of Martin Luther King, Jr., and Its Sources. Miller explained that King grew up in the folk-preaching tradition – beginning with watching his father – in which borrowing words was not only encouraged but expected, and language was not thought of as proprietary.

 

Excessive originality, in fact, was seen as self-centered, if not downright suspicious. The idea of ‘preaching to the choir’ – an expression that connotes a redundant message – was a good thing. Listeners expected the reinforcement and recharging of lessons with authority and familiarity, not originality. Sermons were treated like songs, shared and adapted readily for an audience that expected to hear a version of the hits. ‘My father went to seminary at the same time King did,’ Miller told me, ‘and he actually borrowed from some of the same books of sermons.’

 

The importance of borrowing has often been missed in King scholarship. Entire books have been written on the 1963 ‘I Have a Dream’ speech and not even mentioning that the famously off-script crescendo (repeating ‘let freedom ring from . . .’) was adapted from the conclusion of an address given by King’s friend Archibald Carey Jr. in 1952, which itself echoed the conclusion of a speech by investigative journalist and activist Ida B. Wells in 1893. (‘I’d used in many times before,’ King said later).

   

Borrowing was so common that mid-twentieth century preachers would occasionally pester one another to publish their sermons so that they could be riffed upon, like jazz standards. One distinguished New York City minister repeatedly welcomed King to his pulpit, after King reworked and published a version of that preacher’s own sermon.  Another pastor was an editor at a magazine that published a King homily based on that pastor’s own work. Preachers regularly accepted this from one another for a good reason: It worked. Acquaintances borrowed from each other, and from popular orators like Fosdick and Hamilton, who published their sermons and preached to millions over the radio. King purposely chose widely used material. It provided Virginia Woolf’s ‘rope’ that must be thrown to the audience if they are to coma along with something new.”  

 

….When King graduated from Morehouse and entered Crozer Theological Seminary, he was surrounded by white people for the first time. His tactic for satisfying professors fit squarely within the folk-preaching tradition: He wrote papers that remixed and repeated back the professors’ own beliefs. He graduated at the top of his class, and received a fellowship and an award given by the faculty to the most outstanding student.

 

After Crozer, King continued to refine his practice of borrowing, remixing, and building on work that he knew his audience already accepted. He did it both in environments where it was acceptable – preaching from the pulpit – and in others where it was decidedly not. Near the top of his 1955 PhD dissertation at Boston University, King highlighted one of his sources: ‘In 1952 a very fine dissertation was done in this school by Jack Boozer.’ That dissertation had been presented to the very same thesis adviser. As ever, King was building on material he knew his target audience had already approved. But. As he did with sermons, King copied some passages directly from Boozer. In the late 1980s researchers at Stanford University’s Kings Papers Project discovered the dissertation plagiarism. Soon it exploded in national headlines, and a Boston University committee was convened to determine whether to revoke King’s doctorate. Ultimately, the committee decided not to strip the degree, because King was not alive to defend himself and because the dissertation still made ‘an intelligent contribution to scholarship.’ Academic papers prize strict originality – to such a degree that they almost never connect with any audience at all. That was no use to King, and he regularly violated the norms of scholarly writing by doing what he had learned in the gospel tradition.”

 

There is an article by Josh Howerton on September 9, 2022 titled On “Sermon Plagiarism” Accusations. And rather ironically, another article by Theodore Pappas in Chronicles magazine for May 1998 titled The Life and Times of the King Plagiarism Story discusses how King’s estate charges licensing fees for using ‘his’ content. Also, there is a Wikipedia page titled Martin Luther King Jr. authorship issues.

 

The image of Dr. King came from Wikimedia Commons.

 

 

Monday, June 15, 2026

Two more silly claims that 95% of the world population fears public speaking


 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

I get extremely irritated when I read claims that almost everyone fears public speaking. At Facebook on June 1, 2026 there is a post from Manish Gupta which states that:

 

“Around 95% of the world’s population has the fear of Public Speaking. It also means that only 5% have the courage to stand up in front of a crowd. Do you want to join the 5% brigade? Do you want to be a part of the select few who walk around confidently with this skill? Do you want to master this one skill which can do wonders in your life? If yes, then do call us right away!”

 

Also, in a 2022 book by Peter J. Copeland titled How to Overcome Work Stress: An Office Survival Guide it is claimed that:

 

“In fact, statistics show that some degree of fear/nervousness in public speaking affects about 95% of all speakers.”

 

But those assertions are without any backing, just ipse dixits.

 

On December 1, 2024 I blogged about Does 95% of the population experience public speaking fear? And my answer was no. There are no surveys covering the whole world. And back on December 20, 2016 I blogged about Bursting the overblown claim that 95% of Americans fear public speaking at some level. On October 23, 2025 I posted on how In the eleventh Chapman Survey of American Fears for 2025, public speaking only was ranked #46 of 67 fears at 33.7%. Detailed results from that survey are:

 

Grand Sum for Very Afraid,

Afraid, and Slightly Afraid  68.5%

Sum for Very Afraid

and Afraid                             33.7% 

Very Afraid                            15.5%

Afraid                                     18.1%

Slightly Afraid                       34.9%   

Not Afraid                             31.4%

Web Blank (Don’t Know)      0.1%

 

That Grand Sum is more than 25% lower than the 95% Mr. Gupta claimed. According to the Wikipedia page on Demographics of the United States the 2025 estimated population is 341,784,857. 21.5% are under 18, so 78.5% are over, for an adult population of about 268,300,000 adults. 33.7% of that is about 90,417,000 people who significantly fear public speaking. Or, using the Grand Sum, about 68.5% or 183,790,000 people fear public speaking at some level. Those real numbers are more impressive statistics than overstated percentages.

 

My cartoon was created in PowerPoint from a globe and monkey at OpenClipArt.

 

 

Sunday, June 14, 2026

A textbook chapter on avoiding plagiarism from a free e-book on public speaking


 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

The freely downloadable 2018 fourth edition of the Exploring Public Speaking e-book has a Chapter 26 titled Avoiding Plagiarism. It discusses three types: stealing, sneaking, and borrowing. Stealing is wholesale, it involves taking the entire text.

 


 

 

 

 

 

 

 

 

 

Sneaking involves shuffling the order of sentences. Borrowing is more subtle.

 

Images of a robber and shuffling cards came from Wikimedia Commons.

 

 

Friday, June 12, 2026

My dad told me to use a banana to clean my shoes, and I can’t believe it worked. Now, how do I get these chimps to stop following me around?


 

 

 

 

 

 

 

 

 

 

When I recently looked at Apple News on my iPhone I found an article by Pallavi Mehra at Apartment Therapy from June 4, 2026 with the clickbait title of My Dad Told Me to Use a Banana to Clean My Shoes, and I Can’t Believe It Worked.

 

What about side effects? That title should be followed by asking: How do I get these chimps to stop following me around?

 

The cartoon chimp and grass came from OpenClipArt.

 

Thursday, June 11, 2026

What Is Selective Mutism?


 

 

 

 

 

 

 

 

 

 

 

 

 

 

There are two articles in Toastmaster magazine that discuss an uncommon childhood anxiety disorder called selective mutism. One by Avery Matteo in the latest June 2026 issue on page 8 is titled How I Found My Voice. She said:

 

“Some of my earliest memories are shaped by my experiences with selective mutism, an anxiety disorder that makes speaking to unfamiliar people feel impossible. Public spaces were overwhelming, and even small interactions—such as asking a question to my teacher at school or expressing a need—felt out of reach.”

 

Another article by Jolene Stockman in the July 2019 issue on page 11 is titled Fitting In As An Autistic Speaker. Her third sentence said:

 

“We didn’t know it yet, but we were the founding members of Ngāmotu Breakfast Toastmasters, a club that would remain active 20 years later and took me from school kid with selective mutism to Distinguished Toastmaster and TEDx speaker.”

 

Wikipedia has an article on selective mutism, and there is a Selective Mutism Association with an article titled What is SM? There is a blog post by Anthony D. Smith at Psychology Today on March 7, 2026 titled What You Should Know About Selective Mutism. And the National Health Service [NHS] UK has a February 17, 2023 article on Selective Mutism beginning with the following description:

 

“Selective mutism is an anxiety disorder where a person is unable to speak in certain social situations, such as with classmates at school or to relatives they do not see very often.

It usually starts during childhood and, if left untreated, can persist into adulthood. A child or adult with selective mutism does not refuse or choose not to speak at certain times, they're literally unable to speak. 

The expectation to talk to certain people triggers a freeze response with feelings of anxiety and panic, and talking is impossible. In time, the person may learn to anticipate the situations that provoke this distressing reaction and do all they can to avoid them.

However, people with selective mutism are able to speak freely to certain people, such as close family and friends, when nobody else is around to trigger the freeze response. Selective mutism affects about 1 in 140 young children [~0.7 %]. It's more common in girls and children who have recently migrated from their country of birth.”

 Finally, there is a long article by Chaya Rodrigues-Pereira et al. in European Child & Adolescent Psychiatry on December 1, 2021 (Volume 32, number 10, pages 1821 to 1839) titled Diagnosing selective mutism: a critical review of measures for clinical practice and research.

 

The ‘speak no evil’ monkey image was adapted from Wikimedia Commons.