The least questioned assumptions are often the most questionable. ~ Paul Broca
Above all else French physician and surgeon Paul Broca (1824–1880) found what he was looking for. Despite his use of scientific methods, Broca’s biases went unchecked. Olfaction, for instance, Broca considered a sign of animality. Speech – now there’s something human.
Broca belonged with the brain localization adherents of his day. He employed the clinical method: observing behaviors which led him to hypothesize the brain area involved.
One of Broca’s eventual patients was admitted to Bicêtre, the hospital near Paris for the insane, in 1831. The patient’s sole defect was inability to talk; otherwise his mental functions appeared to be normal. He communicated intelligently using sign language.
After a 30-year residence at Bicêtre, the patient was put under Broca’s knife because of a gangrenous infection.
Broca took an interest in the patient’s speech deficiency, examining him for 5 days, during which Broca satisfied himself that the patient’s vocal inarticulacy had no origin in physical function associated with speech.
On the 6th day, the patient fortuitously died, whereupon Broca performed an autopsy. Broca found a lesion in a specific location. Broca declared this the cause of the patient’s silence: a region now honored with the title Broca’s area, and thereafter linked to speech production.
Broca’s brain work was not confined to spotting speech. Convinced that there was a relationship between brain size and intelligence he took a tape measure to proving it. Broca’s unsurprising conclusion:
In general, the brain is larger in mature adults than in the elderly, in men than in women, in eminent men than in men of mediocre talent, in superior races than in inferior races. Other things being equal, there is a remarkable relationship between the development of intelligence and the volume of the brain.
This tripe, despite Broca knowing numerous facts which contradicted his conclusion, including intelligent women, numskulled large-brained criminals, and smart-but-small-brained Asians, among other instances.
An autopsy found Broca’s brain size, at 1,424 grams, indicative of mediocrity.