Mr. Leborgne was nicknamed “Tan” because it was the only word he could say. When he died in 1861, Paul Broca dissected his brain and found a lesion in the left hemisphere which, he concluded, had been responsible for Leborgne’s loss of speech. Today, Leborgne’s brain lives in a jar at the Musée Dupuytren in Paris, France. And to this day, no one knows his first name.

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