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Oh the humanity!

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Ah... humanity...

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It’s a trainwreck,[br]but I can’t look away.

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It’s 1843, and a debate is raging [br]among physicians

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about one of the most common [br]killers of women: childbed fever.

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Childbed fever strikes [br]within days of giving birth,

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killing more than 70% of those infected—[br]and nobody knows what causes it.

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Obstetrician Charles Meigs has a theory.

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Having observed abdominal inflammation

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in patients who go on [br]to develop the fever,

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he claims this inflammation [br]is the cause of childbed fever.

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Much of the medical establishment[br]supports his theory.

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Oh, come on!

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They really leave me no choice [br]but to teach them some skepticism.

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That’s better.

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Now, Meigs, your argument is based [br]on a fallacy— the false cause fallacy.

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Correlation does not imply causation:

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When two phenomena regularly occur[br]together,

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one does not necessarily [br]cause the other.

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So you say women who have inflammation[br]also come down with childbed fever,

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therefore the inflammation [br]caused the fever.

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But that’s not necessarily true.

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Yes, yes, the inflammation comes first,[br]then the fever,

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so it seems like the inflammation [br]causes the fever.

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But by that logic, since babies [br]usually grow hair before teeth,

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hair growth must cause tooth growth.

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And we all know that’s not true,[br]right?

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Actually, don’t answer that.

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A couple of different things [br]could be going on here.

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First, it’s possible that fever [br]and inflammation are correlated

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purely by coincidence.

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Or, there could be a causal relationship[br]that’s the opposite of what you think—

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the fever causes the inflammation,

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rather than the inflammation [br]causing the fever.

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Or both could share a common [br]underlying cause you haven’t thought of.

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If I may, just what do you think [br]causes inflammation? Nothing?

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It just is? Really?

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Humor me for a moment in discussing[br]one of your colleague’s ideas—

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Dr. Oliver Wendell Holmes.

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I know, I know, [br]you don’t like his theory—

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you already wrote [br]a scathing letter about it.

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But let’s fill your students in, shall we?

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Holmes noticed a pattern: [br]when a patient dies of childbed fever,

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a doctor performs an autopsy.

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If the doctor then treats a new patient,

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that patient often comes [br]down with the fever.

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Based on this correlation

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between autopsies of fever victims[br]and new fever patients,

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he proposes a possible cause.

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Since there’s no evidence that the autopsy[br]causes the fever beyond this correlation,

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he doesn’t jump to the conclusion [br]that autopsy causes fever.

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Instead, he suggests that doctors [br]are infecting their patients

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via an invisible contaminant [br]on their hands and surgical instruments.

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This idea outrages most doctors, [br]who see themselves as infallible.

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Like Meigs here, who refuses [br]to consider the possibility

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that he’s playing a role [br]in his patients’ plight.

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His flawed argument doesn’t leave any [br]path forward for further investigation—

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but Holmes’ does.

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It’s 1847, and physician Ignaz Semmelweis

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has reduced the number [br]of childbed fever deaths

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in a clinic from 12% to 1% [br]by requiring all medical personnel

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to disinfect their hands after autopsies[br]and between patient examinations.

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With this initiative, he has proven[br]the contagious nature of childbed fever.

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Ha!

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It’s 1879, and Louis Pasteur [br]has identified

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the contaminant responsible [br]for many cases of childbed fever:

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Hemolytic streptococcus bacteria.

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Hmm, my fries are cold.

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Must be because my ice cream melted.