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Early internal combustion engines were subject to “knocking,” a metallic rattle that indicated something wasn’t right. GM engineer Thomas Midgley was assigned the task of identifying the cause and the cure. It turned out that knocking was caused by premature combustion in the engine, and the solution Midgley and GM hit upon was a fuel additive: tetraethyl lead. Soon car and airplane engines everywhere were fueled by leaded gasoline. Midgley went on to a second triumph: the development of chlorofluorocarbons as refrigerants.

By the time of his death in 1944, Midgley was being hailed as one of the eras great inventors. But by the last quarter of the twentieth century, a great effort would be undertaken to undo his inventions.

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Playlist:

Fanfare

Opening Theme

Symphony No. 6 in B minor, “Pathétique”
Composed in 1893 by Pyotr Ilyich Tchaikovsky. Public domain.
Performed by the Czech National Symphony Orchestra. Public domain recording. Source.

Closing Theme 

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Except when otherwise indicated, the contents of this podcast are © and ℗ 2015, 2016, 2017, 2018, 2019, 2020, 2021 by Mark Painter, all rights reserved. Some music and sound effects used by arrangement with Pond 5.

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In the 1920’s, it was widely taken for granted that Western civilization was the pinnacle of human achievement, and that all other cultures were “simpler” and more “primitive.”

A 23-year-old graduate student named Margaret Mead single-handedly upended Western civilization’s self-image through her research of adolescence in Samoa. It turns out that the West is not so advanced that it has nothing to learn, nor the Samoans so “primitive” that they have nothing to teach.

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Playlist:

Fanfare

Opening Theme

“Toot, Toot, Tootsie (Goo’ Bye!)”
Composed in 1922 by Gus Kahn, Ernie Erdman, and Danny Russo. Public domain.

Closing Theme 

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Except when otherwise indicated, the contents of this podcast are © and ℗ 2015, 2016, 2017, 2018, 2019, 2020, 2021 by Mark Painter, all rights reserved. Some music and sound effects used by arrangement with Pond 5.

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Charles Darwin himself noted in The Descent of Man that the development of civilization meant that human evolution by natural selection had in some sense “stopped,” since humans no longer abandon individual members of our species to their own fates, as happens with animals in nature. This led some thinkers to speculate about “eugenics,” what we might call “artificial selection,” as an alternative mechanism to natural selection. Human society could direct human evolution.

But when the eugenics movement started talking seriously about what might be done, the discussion turned ugly. IQ test results were used to “prove” people of other races and cultures were intrinsically less intelligent. Laws were passed to ban interracial marriage, to include racial classifications on birth certificates, to restrict immigration of certain types of people, and even to perform forced sterilizations.

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Playlist:

Fanfare

Opening Theme

“The Entrance of the Gods into Valhalla” from Das Rheingold
Composed in 1869 by Richard Wagner. Public domain.
Performed by the United States Marine Band. Public domain recording. Source.

Closing Theme 

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Except when otherwise indicated, the contents of this podcast are © and ℗ 2015, 2016, 2017, 2018, 2019, 2020, 2021 by Mark Painter, all rights reserved. Some music and sound effects used by arrangement with Pond 5.

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In 1925, the Tennessee legislature made it a criminal offense to teach Darwin’s theory of evolution by natural selection in any publicly funded school.

When high school teacher John Scopes was prosecuted under the law, one of America’s most prominent opponents of evolution, former Secretary of State and Presidential candidate William Jennings Bryan, agreed to assist the prosecution, while America’s most famous criminal defense attorney (and notorious agnostic) Clarence Darrow agreed to defend Scopes. It became the most famous legal case in the United States of the time.

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Playlist:

Fanfare

Opening Theme

“His Eye Is on the Sparrow”
Composed in 1905 by Charles H. Gabriel and Civilla D. Martin. Public domain.

Closing Theme 

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Except when otherwise indicated, the contents of this podcast are © and ℗ 2015, 2016, 2017, 2018, 2019, 2020, 2021 by Mark Painter, all rights reserved. Some music and sound effects used by arrangement with Pond 5.